Advances in heat pump systems:A review
K.J.Chua *,S.K.Chou,W.M.Yang
Department of Mechanical Engineering,National University of Singapore,9,Engineering Drive 1,Singapore 117576,Singapore
a r t i c l e i n f o Article history:
Received 9February 2010
Received in revised form 9June 2010Accepted 11June 2010
Keywords:
Heat pump technologies Vapour compression cycle Heat recovery Energy ef?ciency
Hybrid heat pump systems Applications and solutions
a b s t r a c t
Heat pump systems offer economical alternatives of recovering heat from different sources for use in var-ious industrial,commercial and residential applications.As the cost of energy continues to rise,it becomes imperative to save energy and improve overall energy ef?ciency.In this light,the heat pump becomes a key component in an energy recovery system with great potential for energy saving.Improving heat pump performance,reliability,and its environmental impact has been an ongoing concern.Recent progresses in heat pump systems have centred upon advanced cycle designs for both heat-and work-actuated systems,improved cycle components (including choice of working ?uid),and exploiting utilisation in a wider range of applications.For the heat pump to be an economical proposition,continuous efforts need to be devoted to improving its performance and reliability while discovering novel applications.Some recent research efforts have markedly improved the energy ef?ciency of heat pump.For example,the incorporation of a heat-driven ejector to the heat pump has improved system ef?ciency by more than 20%.Additionally,the development of better compressor technology has the potential to reduce energy consumption of heat pump systems by as much as 80%.The evolution of new hybrid systems has also enabled the heat pump to perform ef?ciently with wider applications.For example,incorporating a desiccant to a heat pump cycle allowed better humidity and temperature controls with achievable COP as high as 6.This review paper provides an update on recent developments in heat pump systems,and is intended to be a ‘‘one-stop”archive of known practical heat pump solutions.The paper,broadly divided into three main sections,begins with a review of the various methods of enhancing the performance of heat pumps.This is followed by a review of the major hybrid heat pump systems suitable for application with various heat https://www.doczj.com/doc/a610435224.html,stly,the paper presents novel applications of heat pump systems used in select industries.
ó2010Elsevier Ltd.All rights reserved.
Contents 1.Introduction ........................................................................................................36122.
Improving energy efficiency ...........................................................................................36132.1.Multistage cycles...............................................................................................36132.2.Improving compressor performance ...............................................................................36142.3.Ejector system.................................................................................................36152.4.New refrigerants ...............................................................................................36163.
Hybrid systems......................................................................................................36173.1.Hybrid desiccant system.........................................................................................36173.2.Hybrid solar...................................................................................................36174.
Novel applications/solutions ...........................................................................................36184.1.Desalination...................................................................................................36184.2.Geothermal ...................................................................................................36184.3.Drying .......................................................................................................36204.4.Heating/cooling ................................................................................................36214.5.Cogeneration ..................................................................................................36215.
Conclusions.........................................................................................................3622References .........................................................................................................
3622
0306-2619/$-see front matter ó2010Elsevier Ltd.All rights reserved.doi:10.1016/j.apenergy.2010.06.014
*Corresponding author.Fax:+6567791459.
E-mail address:chuae@https://www.doczj.com/doc/a610435224.html,.sg (K.J.Chua).
1.Introduction
The heat pump(HP)has evolved to become a mature technol-ogy over the past two decades.However,it is not applied as widely as it should or could be.Initial costs,system design and integration remain to be challenging problems,since few major vendors of refrigeration systems offer large-scale heat pumps.Ef?cient use of energy in such energy-intensive operations as district cooling/ heating,drying and cogeneration is crucial to the reduction of net energy consumption and hence emissions of greenhouse gases. With the eventual acceptance of a carbon/energy tax around the world energy,energy conservation will become a key concern in many industrial operations.
With raising cost of fuel and global warming at the forefront of world attention,the interest in HP as a means of energy recovery appears to have been resurrected.Heat pumps offer one of the most practicable solutions to the greenhouse effect.It is the only known process that recirculates environmental and waste heat back into a heat production process;offering energy ef?cient and environmentally friendly heating and cooling in applications rang-ing from domestic and commercial buildings to process industries [1].Practical studies have shown the potential of heat pumps to drastically reduce greenhouse gases,in particular CO2emissions, in space heating and heat generation.The positive impact on envi-ronment depends on the type of heat pump and the energy-mix and ef?ciency of driving power used.
One key approach to improving the energy ef?ciency of many industrial operations is to recover every possible sources of waste heat and turn them to useful outputs.To facilitate this approach, the HP becomes a critical heat system as it possesses the capacity to recover thermal energy,otherwise exhausted to environment, and channel it to places where this heat energy can be converted to produce useful outcomes such as producing hot water to provide heat to occupants in buildings or even for the noble purpose of
Table1
Representative overview of heat pump applications in industrial manufacturing activities(adapted from US Department of Energy[3]).
Industry Manufacturing activity Process Heat pump type
Petroleum re?ning and
petrochemicals Distillation of petroleum and petrochemical
products
Separation of propane/propylene,butane/
butylene and ethane/ethylene
Mechanical vapour compression,open
cycle
Chemicals Inorganic salt manufacture including salt,
sodium sulphate,sodium carbonate,boric acid Concentration of waste streams to reduce
hydraulic load on waste treatment facilities
Mechanical vapour compression,open
cycle
Treatment of process ef?uent Concentration of waste streams to reduce
hydraulic load on waste treatment facilities Mechanical vapour compression,open cycle
Heat recovery Compression of low-pressure steam or vapour
for use as a heating medium Mechanical vapour compression,open cycle
Pharmaceuticals Process water heating Mechanical vapour compression,closed
cycle Wood products Pulp manufacturing Concentration of black liquor Mechanical vapour compression,open
cycle
Paper manufacturing Process water heating Mechanical compression
Paper manufacturing Flash-steam recovery Thermocompression,open cycle
Lumber manufacturing Product drying
Food and beverage Manufacturing of alcohol Concentration of waste liquids Mechanical vapour compression,open
cycle
Beer brewing Concentration of waste beer Mechanical vapour compression,open
cycle
Wet corn milling/corn syrup manufacturing Concentration of deep water and syrup Mechanical vapour compression,open
cycle,thermocompression,open cycle Sugar re?ning Concentration of sugar solution Mechanical vapour compression,open
cycle,thermocompression,open cycle Dairy products Concentration of milk and whey Mechanical vapour compression,open
cycle
Juice manufacturing Juice concentration Mechanical vapour compression,open
cycle
General food-product manufacturing Heating of process and cleaning water Mechanical vapour compression,closed
cycle
Soft drink manufacturing Concentration of ef?uent Mechanical vapour compression,closed
cycle Utilities Nuclear power Concentration of radioactive waste Mechanical vapour compression,open
cycle
Concentration of cooling tower blowdown Mechanical vapour compression,open
cycle Miscellaneous Manufacturing of drinking water Desalination of sea water Mechanical vapour compression,open
cycle
Steam-stripping of waste water or process
streams
Flash steam recovery Thermocompression,open cycle
Electroplating industries Heating of process solutions Mechanical vapour compression,closed
cycle
Concentration of ef?uent Mechanical vapour compression,open
cycle
Textiles Process and wash-water heating Mechanical vapour compression
Space heating Mechanical vapour compression
Concentration of dilute dope stream Mechanical vapour compression General manufacturing Process and wash-water heating Mechanical vapour compression
Space heating Mechanical vapour compression District heating Large-scale space heating Mechanical vapour compression
Solvent recovery Removal of solvent from air streams Mechanical vapour compression,open
cycle
3612K.J.Chua et al./Applied Energy87(2010)3611–3624
desalination.As heat pump continues to?nd new novel applica-tions in various energy-related industries,research efforts have been expanding to make it more energy ef?cient while evolving new hybrid systems that improve overall system ef?ciency.While enough is known about heat pumps and various thermal systems, optimal integration of the technologies remains a challenging R&D task.
Several heat pump types exist;some require external mechan-ical work while others require external thermal https://www.doczj.com/doc/a610435224.html,mer-cial heat pumps based on the vapour compression cycle or the absorption cycle are operational in numerous applications in vari-ous industries.New HP technologies such as the adsorption cycle or the chemical reaction cycle are emerging rapidly,although they have yet to?nd major industrial applications[2].In this paper,se-lected recent works on heat pump systems in various applications and their impact on energy ef?ciency are reviewed.For the pur-pose of discussing key heat pump characteristics and applications, this paper focuses on the mechanical variety rather than the ther-mal types.Table1presents an overview of heat pump applications in industrial processes[3].In contrast to heat actuated systems,it is readily observed that mechanical vapour compression heat pumps are extensively applied in many manufacturing industries. Though this table may not be entirely comprehensive,it highlights the most common industrial applications and heat pump types.
The structure and elements of the review are portrayed in Fig.1. It begins with a section describing various techniques that cur-rently are being employed to improve the performance of heat pump.Next,it presents several hybrid heat pump systems that have the capacity to recover heat from various thermal sources. Lastly,it offers some novel applications of heat pump systems in various energy-intensive industries.Through this review paper on heat pump,we hope to convey one key message,that is,contin-uous efforts in improving heat pump performance will directly optimise energy use and reduce carbon footprint of many en-ergy-intensive operating industries.2.Improving energy ef?ciency
2.1.Multistage cycles
A multistage system employs more than one compression stage. Multistage vapour compression systems can be classi?ed as com-pound or cascade systems[4]as shown in Fig.2.A compound sys-tem consists of two or more compression stages connected in series.It may have one high-stage compressor(higher pressure) and one low-stage compressor(lower pressure)or several com-pressors connected in https://www.doczj.com/doc/a610435224.html,pared to a single-stage system, a multistage has a smaller compression ratio and higher compres-sion ef?ciency for each stage of compression,greater refrigeration effect,lower discharge temperature at the high-stage compressor, and greater?exibility[5,6].The pressure between the discharge pressure of the high-stage compressor and the suction pressure of the low-stage compressor of a multistage system is called inter-stage pressure.Interstage pressure for a two-stage system is usu-ally determined so that the compression ratios are nearly equal between two stages to realize a higher coef?cient of performance (COP)[6].Tanaka and Kotoh[7]investigated the performance of a double-stage compressor heat pump water heaters using CO2 refrigerant for cold districts in Japan.They noted that the ratio of suction pressure(low pressure)of the compressor to the discharge pressure(high pressure)is large and subjects the compressor to harsh operating conditions in cold district where the lowest tem-peratures range fromà10toà20°C.This lowers both the water-heating capacity and the system COP.To improve the performance and reliability of their HP system,they divided the compression stroke into two stages and the refrigerant injection at intermediate pressure[7].Therefore,a compound multi-staging HP system pre-sents a favourable option to improve system COP when operating in extreme cold conditions.
A cascade system consists of two independently operated sin-gle-stage refrigeration systems:a lower system that maintains a
K.J.Chua et al./Applied Energy87(2010)3611–36243613
lower evaporating temperature and produces a refrigeration effect and a higher system that operates at a higher evaporating temper-ature as shown in Fig.2c[4].These two separate systems are con-nected by a cascade condenser in which the heat released by the condenser in the lower system is extracted by the evaporator in the higher system.Wang et al.[8]examined the potential of a dou-ble-stage coupled heat pumps heating system,whereby an air source heat pump was coupled to a water source heat https://www.doczj.com/doc/a610435224.html,-paratively,they found that such a coupling process improved en-ergy ef?ciency ratio by20%compared to a purely air source heat pump[8].
Many of the commercial heat pump systems comprise a single-stage vapour compression cycle.In such systems only one evapora-tor is used for cooling and dehumidifying,and recovering the heat from a heat source.A mechanical constraint is,therefore,imposed on the amount of heat recovered because of the physical area avail-able for heat transfer.Chua and co-workers have conducted studies on a two-stage evaporator heat pump system as shown in Fig.3[9]. In their system,the refrigerant vapour was split into two streams at the exit of the condenser.One stream entered an expansion valve with a higher discharge capacity to regulate to the‘‘low”evaporator temperature while the other entered another expan-sion valve to be expanded to a higher temperature[9].At the high and low pressure evaporators,the evaporation processes took place.The pressure of the refrigerant vapour at the exit of the high pressure evaporator was regulated by a back pressure regulator to that of the low pressure evaporator before mixing at a vapour chamber.Tests conducted the on a prototype two-stage evaporator heat-pump-assisted mechanical drying system highlighted one key ?nding:up to35%more heat could be recovered via a two-stage evaporator heat pump drying cycle in comparison to one having only a single evaporator.The result was an appreciable improve-ment of the heat pump performance[9].
2.2.Improving compressor performance
To minimize the energy consumption of the vapour compres-sion cycle,one key approach is to reduce the energy consumption of the compressor for a required compression ratio.In other words,improve the performance of the compressor.In recent years,one can consider the invention of the scroll compressor to be a major technological breakthrough in compressor technology [10].The scroll compressor is approximately10percent more ef?-cient than the standard reciprocating compressor.There are three chief reasons for this improvement[11].Firstly,the suction and discharge processes are separate,meaning that no heat is added
3614K.J.Chua et al./Applied Energy87(2010)3611–3624
to the suction gas as it enters the compressor in contrast to the reciprocating compressors.Secondly,the compression process is performed slowly over540degrees of rotation versus180degrees of rotation for a reciprocating compressor.Therefore,?uctuations in driven torque are only10percent those of a reciprocating com-pressor.Thirdly,the scroll compression mechanism enables the elimination of the suction and discharge valves which are a source of pressure losses in reciprocating compressors.In additional, scroll compressors have better reliability because they have fewer moving parts and can operate better under liquid slugging condi-tions.Recent works coupling the heat pump with the scroll com-pressor demonstrated the energy ef?ciency of such an integration [12,13].
Recently,a new refrigeration compressor,named‘Revolving Vane(RV)compressor’,has been developed by a group of research-ers[14–17].According to them,the salient feature of their innova-tive design involved the radical use of a rotating cylinder that moved together with the compressing mechanism to cut down on energy loss[14].Consequently,frictional and leakage losses were effectively reduced[14].Compared to piston type,the leak-age loss at the radial clearance in the RV compressor was typically found to be40%lesser than that of the former with anticipated vol-umetric ef?ciencies reaching as high as95%[15–17].The green and novel compressor signi?cantly lowered input energy to perform similar refrigerant compression.Data from experiments have shown energy reduction as high as80%when compared to current systems on the market[14].
A less active approach to enhance compressor performance is to ensure the compressor temperature is kept low during operations. Wang et al.[18]have studied two methods to achieve this.The?rst option involved cooling the compressor’s motor by external means other than using the suction gas.The second option subjected the compressor to undergo an isothermal process by transferring heat from the compression chamber.Results have shown that this strat-egy can potentially reduce the compression work by up to14%as compared to the isentropic compression process for a R22refriger-ation system.A combination of both methods can yield energy sav-ings up to16%depending on operating conditions and?uid choice [18].2.3.Ejector system
The ejector,which is the heart of the jet refrigeration system, was invented by Sir Charles Parsons around1901for removing air from a steam engine’s condenser.In1910,an ejector was used by Maurice Leblanc in the?rst steam jet refrigeration system[19]. The ejector is an essential part in refrigeration and air conditioning, desalination,petroleum re?ning and chemical industries[20].Also, the ejector forms an integral part of distillation columns,condens-ers and other heat exchange processes.Several recent published works have focused on various aspects of the ejector-compression system,namely,ejector-expansion transcritical CO2heat pump cy-cle[21],two-phase ejector system[22,23],ejectors in a multi-evaporator refrigeration[24],and performance of ejector refriger-ation system powered by low grade waste heat or solar[25,26]. The following section highlights one signi?cant recent develop-ment of an ejector heat pump system.
An ejector-compression heat pump employs low-grade thermal energy to provide space cooling and heating[22,23,25].A versatile ejector-compression augmented system is shown in Fig.4.It em-ploys an ejector to perform various degree of compression of the refrigerant,depending on the quality and pressure of the exit refrig-erant from the condenser as well as the available of high tempera-ture waste heat.A gas–liquid separator separates expanded refrigerant into gas and liquid so that gas refrigerant is directly drawn into the compressor at a higher pressure while liquid refrig-erant?ows into the evaporator to exchange heat with the cooled space.The ejector undertakes part of the compression load,enabling the power requirement for the compressor to be signi?cantly re-duced.When high temperature waste heat is available,the ejector is able to undertake the entire compression duty as shown by the dotted-line cycle in Fig.4.Depending on the geometrical,aerody-namical,and mechanical design of the ejector,theoretical study have shown that COP of an ejector-compression heat pump can yield improved performance of up to21%over the vapour compression standard cycle[27].To validate the energy performance of an ejector-compression heat pump,Chaiwongsa and Wongwises[23]designed an experimental setup with motive nozzles having three different outlet diameters.Fig.5shows the coef?cient of performance of their
K.J.Chua et al./Applied Energy87(2010)3611–36243615
ejector-HP system operating at various heat sink temperatures [23].Indeed,their study demonstrated marked improvement in energy ef?ciency with COP approaching as high a value as 6.2.4.New refrigerants
HCFC-22is perhaps the most widely used ?uid in heat pump and air conditioning applications.It has a relatively low ozone-
depletion potential,but since it contains chlorine,therefore,a replacement ?uid is being sought.In seeking for a potential replacement refrigerant,it is important to select one that has ther-modynamic properties similar to the ?uids being replaced.It should also possess the desirable attribute in terms of matching the enthalpy of vaporization.Only when these parameters can be matched closely,the need for system redesign or re-con?guration would be minimal.
Liquid
Gas-liquid separator
3616K.J.Chua et al./Applied Energy 87(2010)3611–3624
Efforts to identify a replacement?uid that has thermodynamic properties similar to HCFC-22have not been particularly success-ful.This has led researchers to investigate the possibility of con-cocting mixtures of HFCs to replace HCFC-22[28].The use of refrigerant mixtures in heat pump and air conditioning systems constantly poses new challenges to engineers.A pure single-com-ponent refrigerant will condense or boil at a constant temperature. In comparison,a refrigerant mixture changes temperature during a constant-pressure condensation or boiling process leading to what is often known as temperature‘‘glide.”The occurrence of glide dur-ing the phase change present problems to heat transfer engineers, among which incomplete condensation is considered the most important one[29].Research continues to foray into refrigera-tion-system component design that can use these phase-change characteristics of refrigerant mixtures.
Besides the issue of environment impact caused by refrigerants, extensive works continue to progress in testing new refrigerant mixtures to improve the energy ef?ciency and operation of heat pumps[30].Recently,performance tests have been conducted on an array of new refrigerant mixtures,namely,R404A[31],R407C [32],R410A[33],R433A[34],R32/R134a[35]and R170/R290 [36].Chen[37]conducted R410A performance evaluation and found that the ef?ciency of the R410A air conditioning unit was ob-served to about12%higher than that of R22unit.Heat pump sys-tems using the new chemical are more ef?cient because compressors that use R410A run cooler.This means they use less energy and are less likely to burn out.In additional,R410A absorbs and releases heat more ef?ciently which means systems using it will use less electricity and operates more ef?ciency[33].Besides positive energy bene?ts,R410A has the potential to reduce heat exchanger sizes,particularly evaporator and condenser,since it captures and releases heat better than R22[37].Another new refrigerant R433A has shown tremendous potential in improving energy ef?ciency of heat pump.Park et al.[34]have conducted R433A and R22comparative test using a heat pump bench testing facility.Key results from their work indicated that the coef?cient of performance of R433A is4.9–7.6%higher than that of HCFC-22 with signi?cantly lower discharge temperature.An extension of this work,they studied the thermodynamic performance of R170/R290mixture as a potential substitute to R22[36].In terms of energy performance,they demonstrated that the COP of R170/ R290mixture was higher than that of R22in the composition range of up to6%R170under typical heat pump operations.
Researchers,such as Atipoang et al.[38]and Gorozabel Chata et al.[39],have studied the performance of hybrid heat pump sys-tems employing refrigerant mixture.They were able determined the best performance of their systems with the right mass mixture of refrigerants.
The future poses a number of challenges and opportunities for manufacturers of HP systems.Most notably is the sustained effort to develop new refrigerants.Concurrently,there will be pressure to improve ef?ciency to maintain the competitive edge over new technologies such as gas heat pumps and to satisfy minimum ef?-ciency requirements imposed by legislations.New performance enhanced refrigerants must compliment improved cycle controls, higher-ef?ciency motors and compressors,and new cycles to real-ize optimum cycle ef?ciencies to meet varying refrigerating capacities.
3.Hybrid systems
3.1.Hybrid desiccant system
A desiccant heat pump hybrid system offers an effective means of controlling space humidity while providing energy-ef?cient air temperature control.Such hybrid systems combine an electric va-pour compression cycle with desiccant material.The desiccant material is regenerated from the waste condenser heat off of the vapour compression cycle.Desiccant systems in HVAC applica-tions,an alternative or supplement to traditional air conditioning systems,are used primarily where the latent load is high or where independent control of temperature and humidity is an important factor[40].Some key advantages of a desiccant heat pump hybrid system include:(1)allowing independent control of humidity and temperatures control for improved comfort and control of space conditions;(2)producing lower humidity levels in occupied spaces provides equivalent comfort levels at space temperatures;and(3) lowering capacity cost by eliminating expensive over-cooling and reheat devices required to dehumidify.
Some commercial applications of such hybrid system include schools,auditoriums,hospitals,low-rise of?ce buildings,super-markets,restaurants,etc.For example,Lazzarina and Castellotti [41]studied how a desiccant heat pump hybrid system performed when employed in a supermarket.In their system,a self-regener-ating liquid desiccant cooling system was integrated to an electric heat pump.Their work demonstrated possible energy savings of such as hybrid system,compared to a traditional mechanical dehu-midi?cation[41].In another independent study,performance mea-surement of a desiccant heat pump was conducted[41].The achievable COP of the unit for low dehumidi?cation capacity(4–6g/kg)was around5–6.However,lower COP was observed with increasing dehumidi?cation capacity.Exploring a novel hybrid sys-tem by the integration of the variable refrigerant?ow and heat pump desiccant(HPD)systems,Aynur et al.[42]conducted?eld performance tests during a heating season.They presented results that demonstrated such a novel system allows signi?cant energy savings while providing the best indoor thermal comfort and in-door quality conditions.
3.2.Hybrid solar
The integration of heat pump with solar technology presents a novel hybrid system whereby the performance of the heat pump can be signi?cantly enhanced by taking heat from a natural source –solar energy[43].The applications for solar-assisted heat pump system include water heating[44–46],heat storage[47]and dry-ing[48].
Among the works conducted on SAHP in recent years,new ideas related to the integrations of solar-thermal,photovoltaic(PV)and heat pump have been conceived to yield novel hybrid systems [49–51].This is primarily due to sustained interest in employing renewable energy to improve heat pumping processes.Pei et al.
[52]have described a novel photovoltaic solar-assisted heat pump (PV-SAHP)system whereby a Photovoltaic Thermal(PVT)was incorporated onto the evaporator to realise an evaporator–collec-tor plate.In their setup,a portion of the solar energy received was converted to electricity while the rest was converted as heat. The heat energy was then absorbed by the refrigerant and carried over to the condenser.The generated electricity serves to augment the compressor power.The COP of the heat pump was also sub-stantially improved because of the solar energy absorption[52]. The results indicated that the PV-SAHP system performed superi-orly over conventional heat pump system while achieving a higher photovoltaic ef?ciency.
As far as the application of SAHP for drying of agricultural prod-ucts is concern,it has been observed that coupling the heat pump to a solar collector improved the thermal ef?ciency of the air col-lector with values spanning0.7–0.75while ef?ciencies of the evap-orator–collector were found to vary between0.8–0.86.Improved ef?ciencies were primarily due to the reduction of losses from the collector[48].Recent works have been devoted to investigating
K.J.Chua et al./Applied Energy87(2010)3611–36243617
the performance of a SAHP for hot water production[45,46].In these works,the solar-assisted heat pump was speci?cally applied to water heating in Hong Kong.A mathematical system model was developed to study its performance under varying operating condi-tions.Results from the model highlighted several key points–SAHP system performance was strongly governed by the change of circulation?ow-rate,solar collector area and initial water tem-perature in the preheating solar tank.It was further demonstrated that the SAHP system could achieve a year-long average COP of 6.46,which is considerably higher than the conventional heat pump system[45].Fig.6illustrates the varying condenser heat gain,compressor input power and system COP during winter sys-tem for water heating in subtropical Hong Kong[45].It was also observed that the amount of hot water produced in summer can be more than double of that in winter.With such favourable en-ergy indicators attributed to its heat recovery capability,the SAHP system is deemed to be economically superior to electrical heating and solar-only systems,and is considered to be competitive with conventional energy-ef?cient fuel burning systems.
4.Novel applications/solutions
4.1.Desalination
Desalination is the process of converting sea water to fresh water.HPs employ heat energy effectively at desalination plants. Several works have been conducted to study the deployment of heat pump systems for producing fresh water[53,54].Desalination plants based on mechanical vapour compression(MVC)technology are inherently the most thermodynamically ef?cient[55].The thermodynamic ef?ciency of the MVC process is derived from the application of the HP principle.A single unit of a two-effect MVC desalination pilot plant of50m3/day capacity was commissioned at Trombay,Mumbai[55].Horizontal tube thin-?lm spray desali-nation evaporators were used for ef?cient heat transfer.The HP application was adeptly applied as the feed water was deemed to be highly saline and condenser cooling water was absent,and where a thermal heat source was not available.The unit produces high-quality water,nearly demineralised quality,directly from seawater.Gao et al.(2008)have demonstrated the energy ef?-ciency of a MVC system to produce freshwater[56].Results from their test-rig demonstrated that freshwater could be produced at a rate60kg/day with a conservative power of500W.
Thermal desalination requires lots of energy.One hybrid tech-nology that can potentially lower energy consumption is solar-as-sisted heat pump as it operates at low temperature and utilizes solar energy,ambient energy and waste heat.Hawlader et al.
[57]have analyzed the performance of a novel solar-assisted heat pump system test-rig and obtained good water production.Their experimental system had the capacity to produce1litre of water per hour.In terms of energy ef?ciency,the hybrid system per-formed ef?ciently had a COP spanning5–9,and a performance ra-tio of0.6–1.38.By virtue of integrating the HP and solar energy,a hybrid system can reduce operating costs with the added bene?t of maintenance being simple and convenient[57].
4.2.Geothermal
A geothermal heat pump or ground-source heat pump(GSHP)is a central heating and/or cooling system that pumps heat to or from the ground to provide heating,air conditioning and,in most cases, hot water[58].They are ideally suited to tap the ubiquitous shal-low geothermal resources.GSHPs include those in which heating/ cooling coils are placed in horizontal and vertical con?gurations, under a building or parking lot as shown in Fig.7.Geothermal HP heating and cooling systems operate as follow:During winter period,they move the heat from the earth into buildings and pump the heat from buildings and discharge it into the ground during summer season.Studies have shown that approximately70per-cent of the energy used in a geothermal heat pump system is renewable energy from the ground[59].The earth’s constant tem-perature is what makes geothermal heat pumps one of the most ef?cient,comfortable,and quiet heating and cooling technologies available today[59].Zam?rescu and Dincer[60]and Granowskii et al.[61]have developed new mechanical compression heat pumps using organic?uids to upgrade the heat and increase the temperature to a level which can run a thermochemical or hybrid cycle.Their heat pumps have demonstrated favourable ef?ciency in applications with a temperature difference of about50°C and where available constant heat source is available,as in the case of the ground-source.
As a renewable energy technology,the GSHP’s high energy ef?-ciency and low environmental impact characteristics have already
3618K.J.Chua et al./Applied Energy87(2010)3611–3624
drawn a fair amount of attention in huge energy-consuming nation like China[62].GSHP can employ both the earth and buried under-ground water as potential heat sources/sinks as shown in Fig.8. The water below the ground level can be the waste water from power plants(e.g.chemical,fossil fuel,etc.)to the wastewater treatment plant[63].The primary advantage of the GSHP technol-ogy is that the both the earth and water stream provides a rela-tively constant temperature for heat transfer,thereby,improving the energy ef?ciency(COP)over that of conventional air systems. Work has also been carried out to integrate ground-coupled heat pump(GCHP)system with a?uid cooler,a cooling tower or surface heat rejecters in cooling-dominated buildings[64].The operation principle of the GCHP system with a cooling tower involves the cooling tower being connected in series with the ground heat ex-changer loop and is isolated from the building and ground loops with a plate heat exchanger.The ground loop is judiciously sized to meet the building heating load and the cooling load in excess of the heating load is met through the supplemental heat rejection [64].
Recent studies have focused on the evaluating the effectiveness of GCHP for heating/cooling applications in buildings while resolv-ing related technical problems[65,66].One study dealt with the modelling and performance evaluation of a heat pump system uti-lizing a low temperature geothermal resource[66].The system was then designed,constructed and tested in Nigde,Turkey,and has been in operation since2005.Energy and exergy analysis methods were used to assess the system performance based on the experimental data.Data analysis illustrated respective energy and exergy ef?ciency values to be ranging from73.9%to73.3% and63.3%to51.7%,respectively[66].Recent research works have also been devoted to studying key parameters that will in?uence the performance of GCHP[67–70].One study emphasized the importance of axial effects for borehole design of geothermal heat pump systems[69].Another study has identi?ed running time, shank spacing,depth of borehole,velocity in the pipe,thermal con-ductivity of grout,inlet temperature and soil type,on the thermal resistance and heat exchange rate,as key parameters that impact on GCHP performance[67].
Better quality of ground-coupled heat pump system installa-tions has also occurred in recent years.Today’s systems typically consist of thermally fused polyethylene or polybutylene piping with an expected lifetime of at least50years[71].Engineers,
K.J.Chua et al./Applied Energy87(2010)3611–36243619
architects,manufacturers,and installers have supported standard-ization of design methods and installation techniques for systems that use horizontal trenches and vertical boreholes[64].Accord-ingly,GSHP’s performance as well as the reliability of the system have improved.
Geothermal heat pumps are durable and require little mainte-nance.They have fewer mechanical components than other sys-tems,and most of those components are underground,sheltered from the weather.The underground piping used in the system is often guaranteed to last25–50years and is virtually worry-free. Geothermal heat pumps are also known to be economically attrac-tive in terms of reducing operating cost to provide heating[70,72]. Employing ground-coupled heat pumps for residential heating and cooling bene?ts the environment.In a CO2emission study con-ducted in Japan,it has shown that a typical residential GSHP pro-duces2038kg-CO2/year[73].This emission amount is less than half compared to conventional oil boiler systems.It is noteworthy that a geothermal heat pump does not create heat by burning fuel like a furnace does.Instead,it collects the earth’s natural heat for various heating applications.As a result,it is one of the cleanest technologies available for transferring heat to and from a natural heat source or sink.To date,geothermal heat pump remains an un-der-used technology,due mainly to the limited awareness of its potential.Therefore,continuous research and publicity efforts will serve to create greater public awareness about its bene?ts and pro-mote end-users con?dence in using it for different heating/cooling applications.
4.3.Drying
Heat pump dryers have been known to be energy ef?cient when used in conjunction with drying operations[9].The principal advantages of heat pump dryers emerge from the ability of heat pumps to recover energy from the exhaust gas as well as their abil-ity to control the drying gas temperature and humidity[74,75]. Researchers have demonstrated the importance of producing a
range of precise drying conditions to dry a wide range of products and improve their quality[2,76,77].Clearly,any dryer that uses convection as the primary mode of heat input to the dryer(with or without supplementary heat input by other modes of heat trans-fer)can be?tted with a suitably designed heat pump(HP). Although batch shelf or tray dryers or kilns(for wood)are the most commonly reported dryers used in conjunction with heat pumps, other types may also be used e.g.?uid beds,rotary dryers etc. The ability of heat pump dryers to convert the latent heat of con-densation into sensible heat at the hot condenser makes them un-ique heat recovering devices for drying applications.The energy ef?ciency of HPD can be re?ected by the higher SMER values and drying ef?ciency when compared to other drying systems as shown in Table2[78].Consequently,higher SMER would then be translated to lower operating cost,making the pay-back period for initial capital considerably shorter.
The key advantages of the heat pump dryer[2]are:(1)heat pump drying(HPD)offers one of the highest Speci?c Moisture Extraction Ratio(SMER),often in the range of1.0–4.0,since heat can be recovered from the moisture-laden air;(2)heat pump dry-ers can signi?cantly improve product quality via drying at low temperatures.At low temperatures,the drying potential of the air can be maintained by further reduction of the air humidity;
Heat from earth
Heat from waste-water
Table2
Comparing heat pump drying with other drying systems(adapted from Perera and Rahman[78]).
Parameter Hot air-
drying
Vacuum
drying
Heat pump
drying SMER(kg water/kW h)0.12–1.280.72–1.2 1.0–4.0
Drying ef?ciency(%)35–4067095
Operating temperature
range(°C)
40–9030–6010–65
Operating%RH range Variable Low10–65
Capital cost Low High Moderate
Running cost High Very high Low
3620K.J.Chua et al./Applied Energy87(2010)3611–3624
(3)a wide range of drying conditions typicallyà20to100°C(with auxiliary heating)and relative humidity15–80%(with humidi?ca-tion system)can be generated;and(4)excellent control of envi-ronment for high-value products and reduced electrical energy consumption for low-value products.
Chua and co-workers have demonstrated the enormous poten-tial of HPD for drying of various bioproducts[79].Besides being en-ergy ef?cient,it provides closed control of the drying conditions in terms of air temperature,humidity and?ow-rate.Instead of employing a constant drying condition throughout the entire pro-cess,heat pump time-varying drying regulates drying tempera-tures in step-wise,intermittent or any cyclic fashions to yield high-quality end bioproducts[79].
In a recent review of heat pump drying technology,HPD and heat pump hybrid systems have clearly proven their capabilities to improve energy ef?ciency for removing similar amount of mois-ture for different products[80].Various researchers involved in drying have found that the HPD uses energy more ef?ciently com-pared with conventional drying systems[2].Hepbasli et al.[81] utilized a gas engine-driven heat pump(GEHP)for food drying pur-poses for the?rst time.The system consists of four key compo-nents,namely:(1)a GEHP unit with heating capacity of18kW, (2)a HP unit with scroll modi?ed for compression with enhanced vapour injection,(3)an air solar collector,and(4)a band conveyor dryer.Preliminary study has indicated that the heat gained by heat recovery can be provided approximately by30%of the total heating capacity for GEHP systems.
There has been a raising trend in applying HPD to various heat-sensitive herbs[82].In comparison to various conventional dryer, heat pump-dried herbs yielded improved colour and aroma of herbs(e.g.parsley,rosemary,and sweet fennel).The sensory val-ues were nearly doubled in case of heat pump-dried herbs com-pared to commercially dried products[2].The speci?c energy consumption(kg/kWh)for herbs drying was also found be low par-ticularly with moisture-laden herbs because greater amount of la-tent heat is available for recovery[2].
The use of modi?ed atmospheres for drying of sensitive materi-als such as food products is another important aspect of the HPD technology[83].Drying with oxygen-sensitive materials such as ?avour compounds and fatty acids can undergo oxidation,giving rise to poor?avour,colour,and rehydration https://www.doczj.com/doc/a610435224.html,ing mod-i?ed atmospheres to replace air would allow new dry products to be developed without oxidative reactions occurring[83].
4.4.Heating/cooling
One of the primary applications of heat pump is to provide heating and cooling to a designated space.The space can vary from a modest size such as a motor vehicle to as large as a township whereby heat can be pumped from one sector to another.Although the application of heat pump technology for heating/cooling is not new,novel applications are still constantly being developed.For example,heating and cooling of space and provision of hot water in a building can be simultaneously being carried out[84].On a lar-ger scale,novel designs of district heating/cooling systems have been recently looked at to support township operations.With im-proved heat pump heating/cooling system designs,energy ef?-ciency for district heating/cooling is signi?cantly enhanced with signi?cant reduction in carbon footprint.
Heat pumps for heating and cooling buildings can be divided into four main categories depending on their operational function and needs.The categories include:(1)heating-only heat pumps, providing space heating and/or water heating;(2)heating and cooling heat pumps,providing both space heating and cooling;
(3)integrated heat pump systems,providing space heating,cool-ing,water heating and sometimes exhaust air heat recovery;and(4)heat pump water heaters,fully dedicated to water heating [84].
Heat pumps can be both monovalent and bivalent[85].A mono-valent heat pump heating system is one whereby the heat pump alone supplies heat during the heating season.In a bivalent heat pump heating system,the heat pump heat capacity may be supple-mented by other heating equipment to meet or assist in meeting heating demand on unusually cold days.In other words,a hybrid heating system comprising heat pump and another heating sys-tem,such as gas or oil boiler,is borne out.Typically,monovalent heat pumps are sized to meet the entire annual heating and cooling demand,while bivalent heat pumps are sized for20–60%of the maximum heat load and meet around50–95%of the annual heat-ing demand[85].
A district heating and cooling system is expected to be a prom-ising energy-saving measure for high-density cities and heat pump systems play an essential role in such large-scale heat transfer operations[86,87].For example,coastal areas are ideal sites for the application of seawater-source heat pump technology(SWHP) to provide district cooling and heating.Recently,Zhen et al.[88] conducted a study on employing heat pumps to deliver thermal energy from the ocean thermal energy to a district in Dalian,China. The district has an estimated68MW heating load and76MW cooling load plant capacity.In this study,the economic,energy and environmental impacts of the SWHP technology were ana-lyzed.Key results from the study indicated that Dalian has great potential for applying SWHP system.It is both technically and eco-nomically feasible because of the favourable geographical location and urban environmental setting[89].Economically,district heat-ing with heat pump system has demonstrated signi?cant reduction in annual energy bill.
Several works have conducted on the performance of heat pump systems employed for motor vehicles[90–92].Antonijevic and Heckt[92]developed a prototype heat pump system for per-formance evaluation in a test vehicle.Test results were obtained, analyzed and compared with other current supplemental vehicle heating systems.The proposed automotive heat pump heating sys-tem performed superiorly compared to other automotive supple-mental heating solutions by demonstrating better performance parameters,lower fuel consumption and stable operational behav-iour.In investigating the performance characteristics of an R134a automotive air conditioning system capable of operating as an air-to-air heat pump using ambient air as a heat source,Hosoz and Direk[90]observed that the heat pump operation provided adequate heating only in mild weather conditions,and the heating capacity dropped sharply with decreasing outdoor temperature. Also,the heat pump yielded a higher coef?cient of performance compared to operating the system purely for air conditioning with a lower rate of exergy destruction per unit capacity.A simple ap-proach to improve the energy ef?ciency of heat pumps in vehicles is by recovering heat from a better heat source such as the engine coolant,exhaust gases[90]or even from the fuel cell stack in the case of fuel cell vehicles[91].
4.5.Cogeneration
At a time of soaring energy costs,cogeneration is one way to ease operating cost.The value of the waste heat dumped into the air or water by power plants can,at times,be worth about twice as much as the electricity that’s generated and sold.Cogeneration systems have a large potential for energy saving,especially when they simultaneously produce heat,cold and power as useful energy outputs.Because of its capacity to recover heat from any heat sources,heat pump plays a critical role in cogeneration.
Typically,cogeneration systems for combined heat,cold and power production are designed mainly incorporating absorption
K.J.Chua et al./Applied Energy87(2010)3611–36243621
heat pumps.But as compression heat pumps become more energy ef?cient,attention has recently been focused at employing them for cogeneration purpose.One such example is the application of heat pump whereby the compression driven by gas engine[93]. Cogeneration systems associated with gas engine-driven heat pump have higher ef?ciency.A recent study on a gas engine heat pump applied to a speci?c building for cogeneration demonstrated effective energy usage.Result of the energy consumption showed that the primary energy ratio of such system was1.49,a perfor-mance index that was much higher than that of the conventional separated production system[93].
A cogeneration system combined with a heat pump can yield impressive carbon savings.Micro-cogeneration,also termed micro combined heat and power or residential cogeneration,is an emerg-ing technology with the potential to provide energy ef?ciency and environmental bene?ts by reducing primary energy consumption and associated greenhouse gas emissions[94].Dorer and Weber [95]compared several micro-cogeneration devices,namely,solid oxide fuel cell,Stirling engine,internal combustion engine,gas boi-ler and ground-coupled heat pump.Taking the gas boiler as the benchmark,they found that CO2mission was the most signi?cant with the heat pump system achieving an appreciable value of up to 29%.Mancarella[96]presented a novel approach to modelling the energy and CO2emission of cogeneration systems coupled to elec-tric heat pumps.One key result from their?ndings was that for small-scale distributed applications heat pump coupled cogenera-tion system exhibited energy saving and emission reduction of the order of up to50%.
Cogeneration can dramatically increase energy ef?ciency,slash carbon emissions,and save money.Heat pump brings about even greater opportunities for enhanced energy ef?ciency.In designing a cogeneration,heat pumps readily compliment with many renew-able energy technologies to produce desired heat and power at re-duced basic fuel input.Thus,integrating heat pumps with clean technologies becomes a potent tool in combating carbon emission. This is the direction energy engineering should be moving with all deliberate speed.
5.Conclusions
Heat pump technologies are widely used for upgrading ambient heat from sustainable sources,such as air,water,the ground and waste heat,to heating temperatures.They can be used for residen-tial and commercial space heating,cooling and water heating, refrigeration and in many industrial processes.In producing heat, they are called heat pumps and they compete with fossil?red boil-ers and direct electric heating.This paper has portrayed HP as an energy-ef?cient technology with enormous potential to contribute to various energy-intensive industries.Table3summarises the key performance values of several reviewed HP works presented in this paper.We have demonstrated through various literature sources how recent efforts have improved heat pump energy ef?ciency by35%through multi-staging and enhanced COP by20%thorough ejector-augmentation.In additional,various recently developed hybrid heat pump systems have further improved ef?cient use of thermal heat,extended the application of HP and markedly re-duced carbon emission.Employing HP for residential heating and cooling produces about2038kg-CO2/year,an amount is less than half compared to conventional boiler systems.
With abundant amount of heat available in various natural sources and waste heat generated in various process industries, HP becomes an indispensable technology that can contribute to-wards a cleaner environment.It is important,when pursing new green technologies to combat climate change,to not lose sight of available conventional technology like the heat pump.Much work has been done but more is still required to integrate HP in innova-tive systems.It is hoped that this review will help increase aware-ness and spur efforts in exploring and maximizing the potential of HP to realize greater energy ef?ciency.
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[96]Mancarella P.Cogeneration systems with electric heat pumps:energy-shifting properties and equivalent plant modelling.Energy Convers Manage 2009;50(8):1991–9. 3624K.J.Chua et al./Applied Energy87(2010)3611–3624 巴尔扎克简介(1799～1850) 法国小说家.1799年5月20日生于巴黎以南的图尔城, 1850年8月18日卒于巴黎.巴尔扎克的一生,处于19世纪前半期的50年,经历了拿破仑帝国的战火纷飞的岁月,动荡不安的封建复辟王朝,以及以阴谋复辟帝制的路易□波拿巴为总统的第二共和国.他用总标题为《人间喜剧》的一系列小说,反映了剧烈的社会变革时期的法国生活. 巴尔扎克出生后不久就被送到附近的乡村去寄养. 上小学后一直到中学毕业,他始终寄住在宿舍里,没有能回 家过一段比较长的日子,享受家庭生活的温暖.离开家庭的童年生活的痛苦使他毕生难忘. 巴尔扎克的父亲原姓巴尔沙,是个精明强干的人. 他来自农村,幼年时跟当地教士学了一点文化,中年致富,在外省当过副市长,供应军粮的承包商,在巴黎经营过呢绒商业,当过巴黎驻军的军需负责人,是一个白手起家的资产者. 1816年,17岁的巴尔扎克结束中学的学业后进大学法科,并在文科旁听.18岁时,先后在诉讼代理人和公证人的办事处当见习生或书记. 从20岁开始,巴尔扎克决定从事文学创作.他在巴黎贫民区租了一间房顶上的阁楼,由父母供给极有限的一点生活费,埋头写作.他的第一部作品是五幕诗体悲剧《克伦威尔》,这是一部完全失败的作品,没有引起任何人的兴趣.接连又写了十多部小说,有的是自己所写,有的是和别人合写.这一阶段他所写的小说全用笔名发表.这些作品并没有给他带来生活所需要的物质条件,他只好暂时放弃文学.1826年借钱出版了一部普及版的《莫里哀全集》,接着又出版一部拉封丹寓言诗集, 销路不佳,亏损负债9,000法郎.后又借债经营印刷厂和铸字厂,均以赔本告终.他前后负债共达6万多法郎. 从1828年夏季开始,巴尔扎克决定重新回到文学事业上来.他写了一部以布列塔尼封建势力武装叛乱反对共和国为题材的小说《最后一个舒昂党人》(后来编入《人间喜剧》,改名《舒昂党的人们》).这是巴尔扎克所写的第一部严肃的文学作品,第一次用巴尔扎克真姓名发表.此书问世,初步奠定了作者在文学界的地位. 接着发表小说《婚姻生理学》,在读者之间引起广泛注意.1831年他的新著《驴皮记》出版,巴尔扎克立即成为法国最负盛名的作家之一. 1819到1829年,是巴尔扎克在文学事业上的探索阶段.从1829年开始,一直到1848年,是他创作《人间喜剧》的时期,也是他文学事业的全盛时期.他用超人的才智与精力,在不到20年的时间内,共创作小说91部.平均每年产生作品四,五部之多.他每日伏案一般都在10小时以上,常常连续工作18小时.有时文思如泉涌,或者为了赶写稿子,他一连几天废寝忘餐,夜以继日地劳动.根据阿尔贝·贝干教授提供的材料,巴尔扎克的杰作《高老头》(原名《高立欧老爹》)是他用三天三夜一气呵成的. 什么是《人间喜剧》的作者的创作动力人们说是因为他负债过多,需要用稿费还债.巴尔扎克年轻时经营印刷出版业确曾负债巨万.但从他成为名重一时的小说家之后,他的收入丰厚,出版商争着和他签订合同,不惜重金预约他尚未完成或尚未动笔的小说稿,早年的债务早已还清.名作家巴尔扎克生活阔绰,醉心于豪华的排场.他在巴黎同时安置了几处住宅和别墅,出门坐最富丽的马车,驾着骏马;仆役都穿制服;他也服饰华贵, 出入于名门大户的沙龙.由此可见,他的勤奋创作,绝对不是由于贫困. 巴尔扎克从年轻时开始就自信有很高的文学才能, 对文学有极大的抱负.他不舍昼夜地勤奋写作,主要因为有一股激情在内心沸腾,促使他充分发挥自己的才能, 要求在文艺界做一番伟大的事业.在他的书室里,有一座作为摆饰的小型拿破仑塑像.在塑像座盘边上,巴尔扎克亲笔写着:"他用宝剑未能完成的大业,我将用笔杆来完成." 巴尔扎克要完成的伟大事业就是《人间喜剧》这座巍峨的文学里程碑.第一次在这位小说家笔下出现《人间喜剧》这个名词是在1813年.毫无疑问,《人间喜剧》的命名是受但丁长诗《神圣喜剧》(中译《神曲》)标题的启发.1841年,巴尔扎克确定了这个庞大的创作计划.当时有四家出版商和巴尔扎克签订合同,合资承包《人间喜剧》的出版工作.1842年,巴尔扎克写了《人间喜剧·导言》,阐述他写作这部史无前例的文学巨著的宗旨.1845年巴尔扎克亲笔写的《人间喜剧总目》,一直保存到现在.根据这个《总目》,《人间喜剧》分为三大部分:《风俗研究》,《哲理研究》和《分析研究》. 《风俗研究》内容最为丰富,包括小说最多.因此这一部分又分为六个门类:1.《私人生活场景》,2.《外省生活场景》,3.《巴黎生活场景》,4.《政治生活场景》, 5.《军队生活场景》,6.《乡村生活场景》.《私人生活场景》包括32部小说,其中4部当时已有提纲,尚未起稿.已经完成的28部之中包括著名的《高老头》(1834), 《猫滚球布店》(1830),《夏倍上校》(1832)和《三十岁的女人》(1831～1834)等.《外省生活场景》包括17 部小说,其中6部尚未完成;已经发表的11部中包括《欧也妮·葛朗台》(1833),《幽谷百合》(1835)和《幻灭》(1837～1843)等.《巴黎生活场景》共有20部小说, 其中6部尚未产生;在已经发表的小说中有《金目少女》 (1834),《纽沁根银行》(1838),《塞沙·皮罗多兴衰记》(1837), 巴尔扎克简介 巴尔扎克（Honore de Balzac，1799～1850），他是19世纪法国伟大的批判现实主义作家，欧洲批判现实主义文学的奠基人和杰出代表。一生创作96部长、中、短篇小说和随笔，总名为《人间喜剧》。其中代表作为《欧也妮·葛朗台》、《高老头》。100多年来，他的作品传遍了全世界，对世界文学的发展和人类进步产生了巨大的影响。马克思、恩格斯称赞他“是超群的小说家”、“现实主义大师”。 巴尔扎克出生于一个法国大革命后致富的资产阶级家庭，法科学校毕业后，拒绝家庭为他选择的受人尊敬的法律职业，而立志当文学家。为了获得独立生活和从事创作的物质保障，他曾试笔并插足商业，从事出版印刷业，但都以破产告终。这一切都为他认识社会、描写社会提供了极为珍贵的第一手材料。他不断追求和探索，对哲学、经济学、历史、自然科学、神学等领域进行了深入研究，积累了极为广博的知识。 1829年，巴尔扎克完成长篇小说《朱安党人》，这部取材于现实生活的作品为他带来巨大声誉，也为法国批判现实主义文学放下第一块基石，巴尔扎克将《朱安党人》和计划要写的一百四五十部小说总命名为《人间喜剧》，并为之写了《前言》，阐述了他的现实主义创作方法和基本原则，从理论上为法国批判现实主义文学奠定了基础。 巴尔扎克在艺术上取得巨大成就，他在小说结构方面匠心独运，小说结构多种多样，不拘一格、并善于将集中概括与精确描摹相结合，以外形反映内心本质等手法来塑造人物，他还善于以精细人微、生动逼真的环境描写再现时代风貌。恩格斯称赞巴尔扎克的《人间喜剧》写出了贵族阶级的没落衰败和资产阶级的上升发展，提供了社会各个领域无比丰富的生动细节和形象化的历史材料，“甚至在经济的细节方面（如革命以后动产和不动产的重新分配），我学到的东西也要比从当时所有职业历史学家、经济学院和统计学家那里学到的全部东西还要多”。（恩格斯：《恩格斯致玛·哈克奈斯》） 巴尔扎克以自己的创作在世界文学史上树立起不朽的丰碑。 某娱乐中心冷冻站设计方案技术经济比较 对某给定工程冷冻站，拟定三种设计方案，分别采用水冷式水机组、风冷热泵式冷热水机组及溴化锂吸收式冷热水机组，从初投资、运行费、折旧费、控制、操作、噪声、振动、运行、管理等方面进行了技术经济比较，并从中选择一种付诸实施。前言 在空调技术快速发展的今天，工程设计中究竟选用哪一种冷（热）水机组？其经济性能、技术性能如何？本文以某工程为例，详细比较了水冷螺杆式冷水机组、风冷热泵螺杆式冷热水机组、直燃型溴化锂吸收式冷热水机组的经济技术性能，希望对工程设计中合理选择冷（热）水机组有所帮助。 工程概况及方案考虑 该娱乐中心为一座3层建筑，局部4层，建筑面积共5620m2。1层为冷冻站、厨房、中西餐厅、美容中心、浴室（内设冷、温、热水冲浪浴池，淋浴等）及客房（内设桑拿浴或按摩浴缸）。2层部分为KTV 包房，其余为客房。3、4层全部为客房。2、3、4层客房均有浴缸等卫生设施。 娱乐中心设有风机盘管空调系统和集中供卫生热水系统。本冷冻站即负担空调系统冷、热量供应和卫生热水系统热量供应。系统冷热负荷见表1。 冷热负荷表1 本工程考虑三个方案。 方案1 选用2台水冷螺杆式冷水机组，设计工况产冷量分别为490KW和324KW，合计814KW，夏季供空调系统冷量；选用一台燃油热水器，设计工况产热量1454KW，夏季供卫生热水系统热量，冬季供空调系统热量和卫生热水系统热量。 方案2 选用一台直燃型溴化锂吸收式冷热水机组，设计工况产冷量805KW，产热量678KW，夏季供空调系统冷量，冬季供空调系统热量；选用一台燃油热水器，设计工况产热量827KW，夏季、冬季供卫生热水系统热量。 巴尔扎克 1、巴尔扎克的文学史地位 巴尔扎克是法国伟大的小说家，是19世纪批判现实主义文学的主要代表。在20年间呕心沥血写作实践中，巴尔扎克在世界文学史上构筑了一座举世无双的巍峨大厦——《人间喜剧》，而他自己则成了“文学中的拿破仑”。 马克思非常推崇巴尔扎克，认为他“对现实关系具有深刻理解”。恩格斯赞誉他的作品有着“了不起的革命辩证法”，并在《致玛·哈克奈斯》一信中对他作了精辟的论述。 2、生平与创作概况 A.全称： xx·xx·巴尔扎克 B.本姓： xx C.生卒____年__月__日： 1799.5.20— 1850.8.18 D.出生地： xx E.家庭： 中产阶级之家 F.教育：1816年结束中学学业 G.主要经历： 1819-1829年，开始写作小说； 1825年起出版图书，开办印刷厂，铸造铅字，以欠债6万法郎告终； 1828-1850年，全力创作《人间喜剧》。 H.主要成就： 包括90余部长篇小说、中篇小说、短篇小说的文学巨著《人间喜剧》。 3、巴尔扎克的创作道路 1819-1829年，探索阶段；1819年，立志当作家。1820年，写作悲剧《克伦威尔》失败，开始创作神怪小说，也未获成功。此后至1828年前，屡屡经商失败，债台高筑。1828年夏起重走文学道路。1929年以真名发表历史小说《朱安党人》，初获成功，在文坛站稳脚跟。 1829-1845年，黄金时代；巴尔扎克怀着做“文学上的拿破仑”的雄心壮志，孜孜不倦地创作，建构着《人间喜剧》这座艺术大厦，接连发表了许多杰作，如《高布赛克》 （1830）、《驴皮记》 （1831）、《xx·xx》 （1833）、《xx》 （1834）、《无神论者做弥撒》 （1836）、《xx银行》 （1837）、《幻灭》（1837-1843）和《农民》 （1845）等。 1846-1850年，晚期。1848年前，巴尔扎克陆续完成了《贝姨》 风冷热泵的选型要点分享 根据风冷热泵的性能和系统分析各种泵的优缺点和适用范围，帮助我们很好选型。 一、根据风冷热泵的性能分析来选型: 1、风冷热泵的冷热量：这两个参数是决定风冷热泵正常使用的最关键参数，它是指风冷热泵的进风温度、进出水温度在设计工况下时其所具备的制冷量或制热量。它可从有关厂家提供的产品样本中查得。但目前在设计中也发现这样的情况，那就是有的厂商所提供的样本参数并未经过测试而是抄自其它厂家的相关样本。这给设计人员的正确选型带来了一定困难。因此笔者建议在有条件的情况下设计人员可根据有关厂家的风冷热泵所配置的压缩机型号，从压缩机生产厂家处获得该压缩机的变工况性能曲线，根据热泵的设计工况查得该压缩机在热泵设计工况下的制冷量和制热量，从而判断该样本所提供参数的真伪。 2、风冷热泵的COP值：该值是确定风冷热泵性能好坏的重要参数，其值的高低直接影响到风冷热泵使用中的耗电量，因此，应尽量选择COP值高的机组。目前我国国家标准是COP值为2.57，多数进口或合资品牌的COP在3左右，个别进口品牌的高效型机组其值可达到3.8。 3、噪声：噪声也是衡量一台风冷热泵机组的重要参数，它直接关系到热泵运行时对周围环境的影响。国内有关专家曾根据工程实测对各类进口热泵的噪声划分为三档，第一档在85dB以上、第二档在 75～85dB之间、第三档在75dB以下。我们在进行工程设计选型中应优先选择噪声在80dB以下的机组。 4、外型尺寸：风冷热泵机组大多布置在室外屋顶，它在进行设备布置时对设备与周围墙面的间距、设备之间的间距都有明确要求，因此我们在进行设备选型时必须考虑所选设备尺寸是否符合设备布置的尺寸要求。在性能相同的前提下应优先选用尺寸较小的机组，以减小设备的占地面积。 5、运行重量：由于风冷热泵机组大多布置在屋面，因此在选型时必须考虑屋面的承重能力，必要时应与结构专业协商，增强屋面的承重能力。但在设备选型时我们应优先选择运行重量较轻的机组。 二、根据风冷热泵的系统分析，了解各种泵的优缺点帮助选型： 所谓风冷热泵的系统分析，就是在风冷热泵的选型过程中除了比较各自的制冷量、制热量、COP值、噪声、运行重量、外形尺寸等参数外，还要对其各自的压缩机型式、冷凝器型式及布置、热力膨胀阀的配置、蒸发器型式、除霜方式、能量调节方式以及热泵系统的自控和安全保护等等加以分析，比较其各自在系统配置方面的优缺点。 压缩机的型式：目前用于风冷热泵的压缩机型式主要有活塞式、涡旋式、螺杆式三种型式。根据热泵工作的特点是运行时间长、压缩比大等情况，笔者认为涡旋式和螺杆式压缩机将成为热泵压缩机的主流。其理由是： 1、涡旋式和螺杆式压缩机较活塞式压缩机具有传动件少，从而使压缩机的磨擦损耗相应减少，整机的效率相应提高。暖通在线 风冷热泵冷热水机组选型应用 编者按：本文阐述了风冷热泵冷热水机组选型中应注意的几方面问题，并对其在工程设计中的几个应注意事项谈了体会。 风冷热泵冷热水机组是九十年代在我国开始应用的一种新型空调主机，此类机组既可供冷又可供热，省却了锅炉房和冷却水系统，安装灵活方便。机组运行采用微电脑控制，可靠性较高。因此在长江流域的许多空调工程中得以广泛采用。但由于各地气候条件不同，再加上工程设计方面也缺少经验。因此在使用中也发现了不少问题。 在进行一个工程的设计过程中，如果当地气候环境允许，同时经过技术经济分析比较后确定该工程空调冷热源采用风冷热泵机组，那么设计人员应该着手对国内外相关厂家的产品进行分析比较，为用户选择一款较为经济合理的热泵产品。选型的主要内容首先是机组的总体性能分析，它包括热泵机组的制冷量、制热量、COP值、噪声、外形尺寸、运行重量等参数。其次，分析该类热泵的内部配置，它包括压缩机型式、冷凝器结构及布置、热力膨胀阀的配置、蒸发器型式、能量调节方式、融霜方式、安全保护及自动控制项目等等。在进行上述分析比较后我们就可以选择一款较为理想的机组，接下来的工作就是进行设备布置，这过程中我们必须考虑设备之间的合理间距，辅助热源的配置以及多台热泵整体运行噪声对周围环境的影响等。下面就以上几方面的问题分别加以阐述。 风冷热泵的性能分析 风冷热泵的冷热量：这两个参数是决定风冷热泵正常使用的最关键参数，它是指风冷热泵的进风温度、进出水温度在设计工况下时其所具备的制冷量或制热量。它可从有关厂家提供的产品样本中查得。但目前在设计中也发现这样的情况，那就是有的厂商所提供的样本参数并未经过测试而是抄自其它厂家的相关样本。这给设计人员的正确选型带来了一定困难。因此笔者建议在有条件的情况下设计人员可根据有关厂家的风冷热泵所配置的压缩机型号，从压缩机生产厂家处获得该压缩机的变工况性能曲线，根据热泵的设计工况查得该压缩机在热泵设计工况下的制冷量和制热量，从而判断该样本所提供参数的真伪。 风冷热泵的COP值：该值是确定风冷热泵性能好坏的重要参数，其值的高低直接影响到风冷热泵使用中的耗电量，因此，应尽量选择COP值高的机组。目前我国国家标准是COP 风冷热泵机组 风冷热泵机组工作原理 风冷热泵机组特点 风冷热泵机组性能分析 风冷热泵机组系统分析 风冷热泵机组安全保护与控制 风冷热泵机组工程设计 风冷热泵机组工作原理 风冷热泵机组特点 风冷热泵机组性能分析 风冷热泵机组系统分析 风冷热泵机组安全保护与控制 风冷热泵机组工程设计 风冷热泵机组工作原理 风冷热泵机组是由压缩机——换热器——节流器——吸热器——压缩机等装置构成的一个循环系统。冷媒在压缩机的作用下在系统内循环流动。它在压缩机内完成气态的升压升温过程（温度高达100℃），它进入换热器后释放出高温热量加热水，同时自己被冷却并转化为流液态，当它运行到吸热器后，液态迅速吸热蒸发再次转化为气态，同时温度下降至零下20℃——30℃，这时吸热器周边的空气就会源源不断地将低温热量传递给冷媒。冷媒不断地循环就实现了空气中的低温热量转变为高温热量并加热冷水过程。 风冷热泵机组特点 1.风冷热泵机组属中小型机组，适用于200-10000平方米的建筑物。 2.空调系统冷热源合一，更适用于同时采暖和制冷需求的用户，同时省去了锅炉房。 3.机组户外安装，省去了冷冻机房，节约了建筑投资。 4.风冷热泵机组的一次能源利用率可达90%，节约了能源消耗，大大降低了用户成本。 5.无须冷却塔，同时省去了冷却水泵和管路，减少了附加设备的投资。 6.无冷却水系统动力消耗，无冷却水损耗，更适用于缺水地区。 风冷热泵机组性能分析 冷热量 这个参数是决定风冷热泵正常使用的最关键参数，它是指风冷热泵的进风温度、进出水温度在设计工况下时其所具备的制冷量或制热量。它可从有关厂家提供的产品 样本中查得。但目前在设计中也发现这样的情况，那就是有的厂商所提供的样本参数并未经过测试而是抄自其它厂家的相关样本。这给设计人员的正确选型带来了一定困难。因此笔者建议在有条件的情况下设计人员可根据有关厂家的风冷热泵所配置的压缩机型号，从压缩机生产厂家处获得该压缩机的变工况性能曲线，根据热泵的设计工况查得该压缩机在热泵设计工况下的制冷量和制热量，从而判断该样本所提供参数的真伪。 COP值 该值是确定风冷热泵性能好坏的重要参数，其值的高低直接影响到风冷热泵使用中的耗电量，因此，应尽量选择COP值高的机组。目前我国国家标准是COP值为2. 57，多数进口或合资品牌的COP在3左右，个别进口品牌的高效型机组其值可达到3.8。 噪声 噪声也是衡量一台风冷热泵机组的重要参数，它直接关系到热泵运行时对周围环境的影响。国内有关专家曾根据工程实测对各类进口热泵的噪声划分为三档，第一档在85dB以上、第二档在75～85dB之间、第三档在75dB以下。我们在进行工程设计选型中应优先选择噪声在80dB以下的机组。 外型尺寸 风冷热泵机组大多布置在室外屋顶，它在进行设备布置时对设备与周围墙面的间距、设备之间的间距都有明确要求，因此我们在进行设备选型时必须考虑所选设备尺寸是否符合设备布置的尺寸要求。在性能相同的前提下应优先选用尺寸较小的机组，以减小设备的占地面积。 运行重量 由于风冷热泵机组大多布置在屋面，因此在选型时必须考虑屋面的承重能力，必要时应与结构专业协商，增强屋面的承重能力。但在设备选型时我们应优先选择运行重量较轻的机组。 风冷热泵机组系统分析 风冷热泵机组的系统分析，就是在风冷热泵的选型过程中除了比较各自的制冷量、制热量、COP值、噪声、运行重量、外形尺寸等参数外，还要对其各自的压缩机型式、冷凝器型式及布置、热力膨胀阀的配置、蒸发器型式、除霜方式、能量调节方式以及热泵系统的自控和安全保护等等加以分析，比较其各自在系统配置方面的优缺点。 压缩机的型式： 巴尔扎克作品经典语录大全100句 1、男子的才对于德而言，就和美貌之于女子差不多：能给人以希望。——巴尔扎克《莫黛斯特·米尼翁婚约》 2、苦难好比一道神奇的符箓，能加强我们的天性，使猜忌与凶恶的人愈加猜忌愈加凶恶，慈悲的人愈加慈悲。——巴尔扎克《夏倍上校》 3、真正的考验是在痛苦和幸福上。当两个人通过了这两种人生的考验，在这过程中每人的优缺点都暴露无遗，也观察了彼此的性格时，他们就可以手携手一直走到坟墓了。——巴尔扎克《莫黛斯特·米尼翁婚约》 4、在爱情方面，别有用心的虚假总比真面目可爱，就因为此，才有许多男人肯在一般手段高明的女骗子身上挥金如土。——巴尔扎克 5、人类所有的力量，只是耐心加上时间的混合。所谓强者是既有意志，又能等待时机。守财奴的生活，便是不断的运用这种力量为自我效劳。他只依赖两种情感：自尊心与利益。但利益既是自尊心的实际表现并且是真正优越的凭据，所以自尊心与利益是一物的两面，都从自私自利来的。这种人物涉及所有的情感，可以说集情感之大成，而我们个个人都跟他们一脉相通。哪有什么全无欲望的人？而没有金钱，哪个欲望够满足？——巴尔扎克《欧叶妮·葛朗台》 6、精神生活与肉体生活一样，有呼也有吸：灵魂吸收另一颗灵魂的感情来充实自己，然后以更丰富的感情送回给人家。人与人之间要没有这点美妙的关系，心就没有了生机：它缺少空气，它会受难，枯萎。——巴尔扎克《欧叶妮·葛朗台》 7、逆境不就是命运的试金石吗? ——巴尔扎克《高 老头》8、"L'amour n'est pas seulement un sentiment, il est aussi un art. 爱不光是一种感情，也是一门艺术。- Honoréde Balzac 巴尔扎克-——巴尔扎克《网络名言集》"9、感情等于才分。感受是了解的对手，正如行动是思维的抗衡。一个有天才的朋友可以通过友情、领会，和他并驾齐驱。一个常人有感情作基础，就可以比倒最伟大的艺术家。这说明女人为什么爱着一些“蠢才”。——巴尔扎克10、到处是真苦难，假欢喜。——巴尔扎克《高老头》11、哪里有穷困，哪里就有苦难。苦难，穷困，蓄势极猛，苦了，穷了，斯滥矣，大权在握，就会滥用，其理自同。——巴尔扎克《乡村医生》12、做点好事，待人要仁慈、宽厚；总之，用你的谦虚来避免厄运吧。——巴尔扎克13、苦难对于人生是一块垫脚石……对于能干的人是一笔财富，对于弱者是个万丈深渊。——巴尔扎克14、目的高尚，会使所做的事情都同样高尚。——巴尔扎克15、实笃一清如水的生活，诚实不欺的性格，不论身处哪个阶级，就算心术最坏的人，也会对之肃然起敬。——巴尔扎克16、长命也许不够好，美好的生命却够长。——巴尔扎克17、人们有多少需求，就能创造多少财富。——巴尔扎克18、艺术就是用最小的面积，惊人地集中最大量思想。——巴尔扎克19、他不断地处于与人奋斗、与天地奋斗之中，没有功夫去尽情卖弄。只有花花公子才会大肆卖弄，迫不及待地将转瞬即逝的一季庄稼收割下来，那种自尊与不管是什么东西，凡从它手下经过就要抽税的海关相差无几。——巴尔扎克20、年轻时费过力气学到的东西，即使是无聊对我们也有用。——巴尔扎克21、拐弯抹角的路成不了 风冷热泵选型及管网流程应用调整 摘要： 通过对风冷热泵机组的研究，了解其构造及基本选型，并根据工程需要对管网系统进行相应改进。 关键词： 模块式风冷热泵、螺杆式风冷热泵、管网流程、蓄水箱 一、引言 最近几年，随着科技的发展，国内的生物医药领域的研发实验室的建设越来越多，尤其是单克隆抗体或疫苗类型的研发实验室。 二、风冷热泵系统概况及选型 目前国内这些医药研发中心通常由办公室、普通实验室、净化实验室三个部分组成，总面积一般都不会太大，基本都控制在6000平方以内。对于办公区和普通实验区来说，中央空调一般都主要用来提供新风，能耗并不大。这两个区域的室内温度调节会通过风机盘管或多联机来满足要求。主要的能耗其实还是集中于净化实验区。 通常来说，在上海、北京、杭州这些国内中心城市，城市发展率较高，空间利用率要求也较高。作为研发性质的生物医药实验室来说，受空间和市政配套限制，不会单独考虑设置冷冻站和锅炉房来作为空调的冷热源，而会选择采用风冷热泵机组。因为风冷型热泵机组有其特点： 1、不需要冷却塔、冷却水泵及冷却水系统； 2、无需专用机房，可直接安装于屋顶或室外合适的空间。 3、智能控制：采用微电脑控制，具有故障诊断、能量管理、防冻监测等多项自动控制功能，确保机组高效运转，操作方便。机组自带485转换接口程序，机组可由上位计算机控制。各台机组的运行可由上位计算机根据负荷需求及运转时间来控制其启停。 4、重量轻、体积小，安装组合简单。 对此，有人可能会提出来一个问题，虽然说是选择风冷热泵，但是具体是选择哪一种风冷热泵呢？是选择模块式的风冷热泵机组、螺杆式风冷热泵机组、离 心式风冷热泵机组中的哪一种呢？ 具体来说，对于目前这种6000平方米以内规模的生物医药实验室来说，采用较多的是螺杆式风冷热泵机组或模块式风冷热泵机组这两种。至于说，具体采用这两种的哪一种，应该说都是可行的，只不过根据业主的考量的方向不一样，也就会有不一样的选择。 下面我来简单介绍一下这两种风冷热泵的特点： 模块式风冷热泵机组螺杆式风冷热泵机组 螺杆式风冷热泵：采用半封闭螺杆式高效压缩机，单机压缩，靠压缩机内的滑阀进行能量调节，结构紧凑，维护方便，运行稳定。出水温度稳定，受天气影响波动幅度小。 模块式风冷热泵机组：采用蜗旋式压缩机，每个模块机组里有2个压缩机，每台压缩机都是独立运行的，一台压缩机坏了，不影响别的压缩机继续使用。多台模块式风冷热泵可以组合在一起使用，一台机组坏了，不影响别的机组运行，控制系统能根据每台机组的运行时间自动调节机组起停，靠机组的运行台数或压缩机的运行个数来进行能量调节。出水温度较稳定，受天气影响波动幅度较小。 从上面两种机器的特性可以看出，如果更多的考虑空调冷冻水的出水温度的稳定性，那么，建议优先考虑螺杆式风冷热泵；如果对空调冷冻水的出水温度的变化幅度没有太高的要求，而重点考虑的是运行过程中能耗的节约，那么，建议优先考虑模块式风冷热泵。 其实，从我个人的角度来说，我建议再增加一个考量因素，那就是洁净室面积所占比重，若洁净室面积所占比重较大，建议优先考虑螺杆式风冷热泵，因为 巴尔扎克出生于一个法国大革命后致富的资产阶级家庭，法科学校毕业后，拒绝家庭为他 选择的受人尊敬的法律职业，而立志当文学家。为了获得独立生活和从事创作的物质保障，他曾试笔并插足商业，从事出版印刷业，但都以破产告终。这一切都为他认识社会、描写 社会提供了极为珍贵的第一手材料。他不断追求和探索，对哲学、经济学、历史、自然科学、神学等领域进行了深入研究，积累了极为广博的知识。 1822年正当巴尔扎克倍受冷遇，痛苦绝望的时刻，结识了贝尔尼夫人。贝尔尼夫人的母亲 曾是王后的侍女，对宫廷的生活，交际的秘密和妇女的命运十分熟悉。贝尔尼夫人比巴尔 扎克大22岁，具有完美的娇柔感，高雅的谈吐，沁人肺腑的同情心，以及慈祥的母爱。这一切深深吸引着巴尔扎克，使巴尔扎克感受到从小没有领略过的母爱般的温情。她对他的 一生产生了重大的影响。巴尔扎克把她称为他的母亲、朋友、家属、伴侣和顾问。[1] 1829年，巴尔扎克完成长篇小说《朱安党人》。历史小说《朱安党人》（1829）是巴尔扎 克用真名发表的 奥诺雷·德·巴尔扎克 第一部作品，描述1800年法国布列塔尼在保皇党煽动下发生的反对共和国政府的暴动。作者赋予英勇的共和国军人以应有的光彩，但也大大美化了朱安党首领孟多兰侯爵，表现出 他当时对贵族的同情。为了写这部小说，他曾细心研究有关暴动的历史文献，亲自去布列 塔尼调查山川形势和农民生活，访问暴动的目击者和参加者，还从友人柏尔里公爵夫人那 里收集许多关于朱安党人的掌故。从写神怪小说过渡到写历史小说，是巴尔扎克走向批判 现实主义的第一个重要步骤。他在《朱安党人》中描写的不是古代历史，而是属于当代社 会生活范畴的重要事件。着重反映当代社会生活，正是巴尔扎克日后所写的《人间喜剧》 的一个特点。 从1829年写《朱安党人》起，巴尔扎克的创作开始进入成熟时期，即《人间喜剧》时期（1829-1848）。在三、四十年代，他除致力于文艺创作以外，还出入巴黎上流社会的沙龙，为几种报刊撰稿，他接触的生活面非常广泛。[2] 巴尔扎克从这时期起，就在现实主义理论方面进行深入探索。他认为小说家必须面向现实 生活，使自己成为当代社会的风俗史家；又认为小说家的任务不仅在于摹写社会现象，还 须阐明产生这些现象的原因，指出人物、 影视剧中奥诺雷·德·巴尔扎克 欲念和事件背后的意义。在塑造人物的问题上，他强调特性，也强调共性；他说诗人的使 命在创造典型，使典型个性化，个性典型化；又说典型人物应该把那些多少和他类似的人 的性格特点集于一身。他还强调艺术必须为社会服务；认为艺术家不仅描写罪恶和德行， 而且要指出其中的教育意义；艺术家必须同时是道德家和政治家。 1830年4月，巴尔扎克《人间喜剧》中《私人生活场景》两卷出版了。然而，他深深地为 法国文学创作者的处境担忧。虽然法国于1791年颁布的《表演法令》和1793年颁布的 致领导函 尊敬的XXX领导： 您好！ 非常感谢贵单位给我公司提供的这次参与空调系统说明的机会。多年来，清华同方秉承清华大学“自强不息、厚德载物”的校训，不以纯粹的出售产品为目的，而是以向广大顾客提供最适合其本身特点要求的服务为最高宗旨，竭尽全力、精益求精使企业取得了长足的发展，赢得了广泛的赞誉。 清华同方是具有新型空调设计、开发、制造、工程安装等综合服务能力为一体的高科技公司，以清华大学的高技术人才为依托，始终保持领先一步的技术优势。产品质量和工程安装质量也已在人民大会堂、故宫博物院、中央电视台、毛主席纪念堂、中国国际航空公司等数百项国家重大工程中经受住了严格的考验和检验。清华同方产品的先进性、质量的可靠性、服务的有效性已得到广泛的认证和中央领导人的认可。 我公司根据贵方工程概况及地理特点，本着合理、科学、用户至上的原则向贵方推荐： 二十一世纪最有效的供暖、空调技术 ——清华同方GHP型水源中央空调系统 2009年4月 二十一世纪最有效的供暖、空调技术 ——节能环保型水源热泵空调系统 地源热泵是一种利用地表浅层地热资源（也称地能，包括土壤、地下水和江、河、湖、海以及城市污水等）作为冷热源的即可供热又可制冷的高效、节能、环保的空调系统。地源热泵利用浅层地能温度相对稳定的特性，通过输入少量的高品位能源（如电能），使建筑达到供热或制冷的目的。地源热泵可以取代锅炉或市政管网等传统的供暖方式和中央空调系统。地能分别在冬季作为热泵供暖的热源和夏季空调的冷源，即在冬季，把地能中的热量“取”出来，提高温度后，供给室内采暖；夏季，把室内的热量取出来，释放到地能中去。地源热泵消耗1KW的能量，用户可以得到4KW以上的热量或冷量。同时，它还可以供应给生活用水，是一种有效地利用能源的方式。 污水、井水、费水、费冷、费热、综合利用 根据现场调查，特向甲方提供节能减排最佳方案： 1、夏季制冷时，抽取地下低温井水通过机组吸取水冷量后送至其它生产设备循环利用。 也可利用生产设备产生的费冷，通过机组吸收费冷循环利用。 2、冬季制热时，利用生产设备排出高温污水吸取热量后送至污水处理车间。 风冷热泵机组： 风冷热泵机组是由压缩机——换热器——节流器——吸热器——压缩机等装置构成的一个循环系统。冷媒在压缩机的作用下在系统内循环流动。它在压缩机内完成气态的升压升温过程（温度高达100℃），它进入换热器后与风进行热量交换，被冷却并转化为流液态，当它运行到吸热器后，液态迅速吸热蒸发再次转化为气态，同时温度下降至零下20℃——30℃，这时吸热器周边的空气就会源源不断地将低温热量传递给冷媒。冷媒不断地循环就实现了空气中的低温热量转变为高温热量并加热冷水过程。 特点： 1.风冷热泵机组属中小型机组，适用于200-10000平方米的建筑物。 2.空调系统冷热源合一，更适用于同时具有采暖和制冷需求的用户，省去了锅炉房。 3.机组户外安装，省去了冷冻机房，节约了建筑投资。 4.风冷热泵机组的一次能源利用率可达90%，节约了能源消耗，大大降低了用户成本。 5.无须冷却塔，同时省去了冷却水泵和管路，减少了附加设备的投资。 6.风冷系统替代冷却水系统，更适用于缺水地区。 性能： 冷热量 这个参数是决定风冷热泵正常使用的最关键参数，它是指风冷热泵的进风温度、进出水温度在设计工况下时其所具备的制冷量或制热量。它可从有关厂家提供的产品样本中查得。但在设计中也发现这样的情况，那就是有的厂商所提供的样本参数并未经过测试而是抄自其它厂家的相关样本。这给设计人员的正确选型带来了一定困难。因此笔者建议在有条件的情况下设计人员可根据有关厂家的风冷热泵所配置的压缩机型号，从压缩机生产厂家处获得该压缩机的变工况性能曲线，根据热泵的设计工况查得该压缩机在热泵设计工况下的制冷量和制热量，从而判断该样本所提供参数的真伪。 COP值 该值是确定风冷热泵性能好坏的重要参数，其值的高低直接影响到风冷热泵使用中的耗电量，因此，应尽量选择COP值高的机组。我国国家标准是COP值为2.57，多数进口或合资品牌的COP在3左右，个别进口品牌的高效型机组其值可达到3.8。 噪声 噪声也是衡量一台风冷热泵机组的重要参数，它直接关系到热泵运行时对周围环境的影响。国内有关专家曾根据工程实测对各类进口热泵的噪声划分为三档，第一档在85dB以上、第二档在75～85dB 之间、第三档在75dB以下。我们在进行工程设计选型中应优先选择噪声在80dB以下的机组。 外型尺寸 风冷热泵机组大多布置在室外屋顶，它在进行设备布置时对设备 第五节巴尔扎克与《高老头》分析 一、巴尔扎克简介（1799-1850） 1、《人间喜剧》的创作：《风俗研究》《哲理研究》《分析研究》，是一部关于19世纪法国的“包罗万象的社会史”。 （1）主题上要写出“一个完整的社会”，艺术上要呈现一个“统一、独创、新鲜的整体”。 （2）主题思想：反映出资产阶级取代贵族阶级的时代潮流。 A、资产阶级的发迹史。《赛查·皮罗托盛衰记》《欧也妮·葛朗台》《纽沁根银行》 B、贵族阶级的衰亡史。《古物陈列室》 C、金钱成为社会的轴心，操纵着社会关系，这不仅反映在广义的政界、社交界等社会层面，而且反映在最亲密的家庭关系中。 （3）艺术特征： A、艺术形式的多样化和富于变化，或客观描述，或转述故事，或深入人们的情感中探讨。 B、在典型环境中塑造具有典型意义的人物形象，人物性格与物质化的社会环境水乳交融。 C、作品文本的相互交织。《人间喜剧》的一部作品中的人物形象会在多部作品中出现，人物的命运具有时间上的连续性，因而众多作品相互勾连，构成一部完整的社会生活的记录。如《高老头》中鲍赛昂夫人的凄凉结局、拉斯蒂涅的飞黄腾达。 D、写实与幻想交相辉映，突出金钱统治下的法国社会的疯狂喧嚣。《萨拉辛》 二、《高老头》分析（[法]巴尔扎克著，张冠尧译，北京：人民文学出版社，2003年） 一、作品背景与主要内容介绍 当时的法国现实是，资产阶级已经获得彻底的胜利，而贵族阶级逐渐地退出历史舞台。这样资本主义的生产关系的重要基础即金钱在社会生活中占据着绝对地位，支配着各种社会关系，并且渗透在人们的亲情、友情和爱情中。 《高老头》是法国批判现实主义大师巴尔扎克最具代表性的作品之一，充分展现了金钱的罪恶与对人类美好感情与人性的腐蚀作用。 二、作品简介 作品中有着两条线索，一条是高老头的命运正由盛转向衰败，另一条是拉斯蒂涅正步步高升，但展现的是相同主题。拉斯蒂涅为高老头奔走于两地之间，作品通过他的奔走将这两条线索结合起来，凸现法国巴黎各个社会阶层的生活。从代表着法国社会底层的缩影的伏盖公寓，到法国的上流社会人人趋之若骛的地方鲍赛昂夫人的门庭和舞会；从社会的底层人物伏盖公寓中住客之间的关系，到贵族与银行家的家庭关系，《高老头》描写得详尽细致，淋漓尽致。与法国社会各阶层的接触使拉斯蒂涅逐步认识到法国社会的本质，即金钱至上，人人为己，但这也使他彻底泯灭的人性的良知。 三、作品主题 1、金钱主宰着社会的一切关系 2、高老头的沦落意味着，在资本阶级上升时期金钱对社会的统治和金钱至上的原则的冲击下，传统的宗法制家庭伦理关系彻底解体。 四、拉斯蒂涅的人物形象分析 作者塑造高老头人物形象的意义，不仅是想通过高老头的命运对作品中另一主要人物拉斯蒂涅发生重要的作用，让拉斯蒂涅再一次受到了资产阶级自私自利 风冷热泵机组概述 东盛环保公司提供 风冷热泵机组是由压缩机——换热器——节流器——吸热器——压缩机等装置构成的一个循环系统。冷媒在压缩机的作用下在系统内循环流动。它在压缩机内完成气态的升压升温过程（温度高达100℃），它进入换热器后与水进行热量交换，被冷却并转化为流液态，当它运行到吸热器后，液态迅速吸热蒸发再次转化为气态，同时温度下降至零下20℃——30℃，这时吸热器周边的空气就会源源不断地将低温热量传递给冷媒。冷媒不断地循环就实现了空气中的低温热量转变为高温热量并加热冷水过程。 一．特点 1.风冷热泵机组属中小型机组，适用于200-10000平方米的建筑物。 2.空调系统冷热源合一，更适用于同时具有采暖和制冷需求的用户，省去了锅炉房。 3.机组户外安装，省去了冷冻机房，节约了建筑投资。 4.风冷热泵机组的一次能源利用率可达90%，节约了能源消耗，大大降低了用户成本。 5.无须冷却塔，同时省去了冷却水泵和管路，减少了附加设备的投资。 6.风冷系统替代冷却水系统，更适用于缺水地区。 二．性能 冷热量 这个参数是决定风冷热泵正常使用的最关键参数，它是指风冷热泵的进风温度、进出水温度在设计工况下时其所具备的制冷量或制热量。它可从有关厂家提供的产品样本中查得。但在设计中也发现这样的情况，那就是有的厂商所提供的样本参数并未经过测试而是抄自其它厂家的相关样本。这给设计人员的正确选型带来了一定困难。因此笔者建议在有条件的情况下设计人员可根据有关厂家的风冷热泵所配置的压缩机型号，从压缩机生产厂家处获得该压缩机的变工况性能曲线，根据热泵的设计工况查得该压缩机在热泵设计工况下的制冷量和制热量，从而判断该样本所提供参数的真伪。 COP值 该值是确定风冷热泵性能好坏的重要参数，其值的高低直接影响到风冷热泵使用中的耗电量，因此，应尽量选择COP值高的机组。目前我国国家标准是COP值为2.57，多数进口或合资品牌的COP在3左右，个别进口品牌的高效型机组其值可达到3.8。 噪声 噪声也是衡量一台风冷热泵机组的重要参数，它直接关系到热泵运行时对周围环境的影响。国内有关专家曾根据工程实测对各类进口热泵的噪声划分为三档，第一档在85dB以上、第二档在75～85dB之间、第三档在75dB以下。我们在进行工程设计选型中应优先选择噪声在80dB以下的机组 系统 风冷热泵机组的系统分析，就是在风冷热泵的选型过程中除了比较各自的制冷量、制热量、COP值、噪声、运行重量、外形尺寸等参数外，还要对其各自的压缩机型式、冷凝器型式及布置、热力膨胀阀的配置、蒸发器型式、除霜方式、能量调节方式以及热泵系统的自控和安全保护等等加以分析，比较其各自在系统配置方面的优缺点。 三．压缩机的型式： 用于风冷热泵的压缩机型式主要有活塞式、涡旋式、螺杆式三种型式。根据热泵工作的特点是运行时间长、压缩比大等情况，笔者认为涡旋式和螺杆式压缩机将成为热泵压缩机的主流。其理由是： 1.涡旋式和螺杆式压缩机较活塞式压缩机具有传动件少，从而使压缩机的磨擦损耗相应减 龙源期刊网 https://www.doczj.com/doc/a610435224.html, 巴尔扎克作品中的现实主义风格 作者：梁萧 来源：《现代交际》2016年第01期 摘要：法国文学巨匠巴尔扎克的作品充满了批判现实主义色彩，以写实为基调，成为19 世纪法国社会的一面镜子。他善于在特定环境下塑造典型的、具有代表性的、富有个性化的人物；再通过人物再现的写作手法，折射社会，堪称现实主义写作风格的代表作家之一。他所描绘的现实世界，并非是生活的复制品，而是基于小说家敏锐的观察力，用小说写作手法呈现“真实”的世界。可以说，他是一位创造现实的现实主义作家。 关键词：巴尔扎克；现实主义；写实 中图分类号：G6343文献标识码：A文章编号：1009-5349（2016）01-0140-05 作为现实主义小说的奠基人，巴尔扎克不仅开辟了小说的新天地，更将小说的表现力提升到空前的高度。他强调塑造人物要典型化，从典型化中突出人物个性，再通过典型人物这一个“点”去折射社会现实的一个“面”。他所刻画的人物如“伏脱冷”、高老头的女儿，将个性与共性完美结合，又展现得淋漓尽致，使之成为典型的小说人物。他的作品反映社会现实，以写实为基调，长于描写丰富多彩的生活，刻画的法国社会风俗细致入微，读者通过人物命运的变化，看到了19世纪法国社会所经历的巨变。他通过创造现实来描写“真实”世界的创作模式，被誉为“创造现实的现实主义者”。 一、还原巴尔扎克 巴尔扎克作为现实主义文学巨匠，是塑造典型小说人物的大师。在其二十载的创作生涯中，创作了《高老头》、欧也妮·葛朗台》《幽谷百合》等脍炙人口的不朽之作，而《人间戏剧》更是被誉为“法国社会的百科全书”，真实地呈现了19世纪法国社会中金钱的统治地位，深刻剖析了人性的丑与美，在世界小说史上树立了一块迄今为止仍无法超越的丰碑。[1]与他 同时代的法国文学巨匠维克多·雨果在其葬礼上发表了这样的赞誉：“在最伟大的人物中间，巴尔扎克是第一等的人；在最优秀的人物中间，巴尔扎克是最高的一个。”[2] 尽管巴尔扎克在生前并未得到应有的赞誉，但在其死后，人们逐渐认识到他作品的伟大之处，并将其誉为“现实主义”小说的奠基人。在今天，我们重读巴尔扎克作品时，不禁被其光怪陆离的小说场景、极富个性的人物形象、对现实世界中追逐金钱名利心理的深刻剖析所折服。他的作品兼具了现实主义小说的三大特性，即真实的细节描写、典型的人物形象、客观的叙述方式。要解读巴尔扎克作品，剖析他是如何创作出如此“真实”的小说，首先要还原巴尔扎克，还原他的创作历程。 （一）折射社会的镜子 热泵机组选型指南 热泵机组是一种新型节能的空调制冷装置。 热泵机组实质上是一种能源采掘机械，它以消耗一部分高质能(机械能、电能或高温热能等)为补偿，通过热力循环，把环境介质(水、空气、土地)中贮存的能量加以发掘进行利用。它的工作原理与制冷机相同，都按逆循环工作，所不同的是它们工作的温度范围和要求的效果不同。致冷装置是将低温物体的热量传给自然环境以造成低温环境，热泵则是从自然环境中吸取热量，并将它输送到人们所需要温度较高的物体中去。 热泵的特点：(1)它的突出优点就是热效率高。节能效果显著。这种装置只需耗费少量的高质能(电能、机械功)就可获得较多的热能．因而减少了能源的浪费。(2)热泵技术的采用可取代大量的锅炉房，节省燃料，减少大气的污染。余热得到利用的同时也减少了热污染，因而使城市环境卫生必然得到改善，也有利于生态平衡。 工作原理 在蒸发器中工质蒸发吸取自然水源或环境大气中的热能，经压缩后的工质在冷凝器中放出热量加热供热系统的回水，然后由循环泵送到热用户用作采暖或热水供应等。在冷凝器中，工质凝结成饱和液体，经节流降压降温进入蒸发器，蒸发吸热、气化为干饱和蒸气，从而完成一个循环。 基本组成 热泵机组主要由压缩机、冷凝器、蒸发器、节流装置、四通换向阀等组成热泵，另外还有必需的制冷空调、采暖的室内末端输配系统，包括加压送风系统或地板盘管、风机盘管等。 分类 按热源分：空气源、地下水源、土壤源、太阳能以及排放余热等。 按压缩机种类分：活塞式、螺杆式、涡旋式、离心式。 按热泵的功能分：单纯供热、交替制冷供热、同时制冷供热。 按驱动形式分：电力压缩式、热力吸收式。 按供热温度分：低温（<100℃）、高温（>100℃） 按热源和冷媒介质的组合方式分：空气－空气源热泵、空气－水源热泵、水－水源热泵、水－空气源热泵。 选型指南 1.热泵机组的冷负荷计算方法同于常规空调系统，热负荷计算方法于采暖系统大致相同，但需考虑新风耗热量。 2.选型时要注意当地是否有足够的水源（包括水量、水温及水质）、电源和热源（包括热源性质、品位高低）。巴尔扎克简介
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