Desalination 222 (2008) 646–655
Presented at the conference on Desalination and the Environment. Sponsored by the European Desalination Society and Center for Research and Technology Hellas (CERTH), Sani Resort, Halkidiki, Greece, April 22–25, 2007.An open air–vapor compression refrigeration system for
air-conditioning and desalination on ship
Shaobo Hou a,b *, Huacong Li a , Hefei Zhang a
a
School of Power and Energy, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, China
b
College of Engineering, Guangdong Ocean University, East Jiefang Rd. No. 40, Xiashan,
Zhanjiang, Guangdong 524006, China email: sbhou@https://www.doczj.com/doc/a56729025.html,, sbhou@https://www.doczj.com/doc/a56729025.html,
Received 20 December 2006; accepted 3 January 2007
Abstract
This paper presents an open air–vapor compression refrigeration system for both air-conditioning and desalination on ship cooled by seawater, and proves its feasibility through performance simulation. Pinch technology is used in the analysis of heat exchange in the surface heat exchanger and the temperature difference at pinch point is selected as 6°C. The freshwater is obtained from the dehumidification of the compressed wet air before turbine and the flash and condensation of the cooling water. Its refrigeration depends mainly on both air and vapor, more efficient than a conventional air-cycle, and the use of turbo-machinery makes this possible. This system could use the cool in seawater, which could not be used to cool air directly. Also, the heat rejected from this system could be used for desalination. The sensitivity analysis of COP to h c and h t and the simulated results T 4, T 7, T 8, q 1, q 2 and w m of circle are given. The simulations show that the COP of this system depends mainly on T 7, h c and h t , and varies with T 3 or T wet and that this circle is feasible on ship although the sensitivity of COP to efficiencies of the axial compressor and turbine. The optimum pressure ratio in this system could be lower and this results in a fewer number of stages of axial compressor. The adoption of this system will make air-conditioned room more comfortable because of its very low temperature air obtained. H umid air is a perfect working fluid for central air-conditioning and desalination on ship and no cost to the owner. The system is more efficient because use of cool seawater to cool the air before turbine. In addition, Pinch technology is a good method to analyze the wet air heat exchange with water.
Keywords:Turbo-machinery; Desalination; Air-conditioning units; Natural working fluid; Refrigeration; Pinch
technology
*Corresponding author.
doi:10.1016/j.desal.2007.01.190
0011-9164/08/$– See front matter ? 2008 Published by Elsevier B.V.
S. Hou et al. / Desalination 222 (2008) 646–655647
1. Introduction
The outdoor air temperature on board can reach 27–34°C in south China sea at summer and the relative humidity is nearly 90%. How-ever, the temperature of the seawater 10m below sea level is 18–25°C and that of the sea-water far below sea level could be lower. If the seawater were used to cool air for air-conditioning directly, it is not efficient because of the small temperature difference and large mount of the pump work consumed.
Air compression refrigeration cycle was studied long ago. Several disadvantages pre-vented air from being used as a working fluid in refrigeration. These included low volumetric refrigerating effect, which may result in a large compressor, and low COP due to low efficien-cies of compressor and expander. After CFC’s invention in 1930’s, people pay little attention to actual air compression refrigeration.
Recently, as a result of the destruction of the ozonosphere by chlorofluorocarbon (CFC) and the pressure of environmental protection, research upon air refrigeration cycles has been paid more attention [1–3]. Optimizations of air cycles are also carried out using finite-time thermodynamics (FTT) or entropy-generation minimization (EGM) [4–7].
Chen et al. investigated the cooling-load vs. COP characteristics of a simple [8] and a regener-ated [9,10] air refrigeration cycle with heat-trans-fer loss and/or other irreversibilities. Luo et al. [11] optimized the cooling-load and the COP of a sim-ple irreversible air refrigeration cycle by searching for the optimum pressure-ratio of the compressor and the optimum distribution of heat conductance of the hot- and cold-side heat exchangers for the fixed total heat-exchanger inventory.
Spence et al. [12,13] reported the design, con-struction and testing of an air-cycle refrigeration unit for road transport and performance analysis of a feasible air-cycle refrigeration system for road transport.
Zhou et al. [14–17] presented cooling load density analysis and optimization for an endor-eversible air refrigerator, cooling load density characteristics of an endoreversible variable-temperature heat reservoir air refrigerator, theoret-ical optimization of a regenerated air refrigerator and cooling-load density optimization for a regen-erated air refrigerator.
Chen and Su [18] gave exergetic efficiency optimization for an irreversible Brayton refrigera-tion cycle. Chen et al. [19] presented performance optimization for an irreversible variable-tempera-ture heat reservoir air refrigerator. Williamson and Bansal [20] studied the feasibility of air cycle sys-tems for low-temperature refrigeration applica-tions with heat recovery.
With the development of the aeronautical industry, highly efficient axial compressors and turbines have become a reality. At present, the stagnation iso-entropic efficiencies of a single stage axial compressor and a turbine can reach 0.88–0.91 [21]. High-speed fans have been used in ordinary air-conditioning systems nowadays.
However, the water vapor in the working fluid was not considered in all the above researches [1–20] on air compression refrigeration cycle and the used equipments were centrifugal compressor and centripetal turbine in the most researches, which have low efficiencies than axial compres-sor and turbine. The mount of the water extracted from high pressure wet air can reach 18–30g/kg (d.a.). And the mount of the latent heat discharged from vapor condensed, about 45–75kJ/kg (d.a.), exceeds the sensible heat from air, 30–50kJ/ kg(d.a.).
H ou and Li [22] presented an axial-flow air–vapor compression refrigerating system for air-conditioning, in which wet air is working fluid and axial compressor and turbine were used, but these have not yet attracted people’s attention.
Hou and Zhang [23] presented an axial-flow air–vapor compression refrigerating system for air-conditioning cooled by circulating water, in
648S. Hou et al. / Desalination 222 (2008) 646–655
which wet air is working fluid, an axial com-pressor and a turbine were used and wet air is cooled by circulating water. The paper proved its feasibility through performance simulation and also indicates its advantages. These include the possibility to simplify air-conditioning systems,to reduce the amount of the initial investment of an air-conditioning system and to make air-conditioned rooms more comfortable.
Hou et al. [24] has applied Pinch technology to performance optimization of solar humidifica-tion–dehumidification desalination process suc-cessfully. Hou et al. [25] gave an exergy analysis of solar multi-effect humidification dehumidifi-cation desalination process.
The aim of this paper presents an open sys-tem, which is an open air–vapor compression refrigeration system for both air-conditioning and desalination on ship cooled by seawater,and its performance from simulation. In this open air–vapor refrigeration cycle, the seawater from deeper sea is used. Thus, we could get the lower wet air temperature before turbine. In addition, the energy from the cooling water could be used for desalination. 2. System
Representation on enthalpy–entropy coordi-nates and circuit diagram of an open air-compres-sion refrigeration system for air-conditioning and desalination on ship cooled by seawater are shown in Figs. 1 and 2, respectively.
The outdoor air at 2 is drawn into the atomiz-ing chamber, cooled into the saturated air at 3with some fine water droplet and then com-pressed by an axial compressor. A flow of com-pressed air at 4 with higher temperature, T 4, and high pressure, P 4, is obtained. Then the com-pressed air at 4 is cooled into the saturated air at 7 with a temperature of T 7 by cool seawater in a surface heat exchanger after the axial compressor outlet. Some vapor is condensed to freshwater and latent heat of the vapor discharged from
4to 7. Then the saturated air at 7 is expanded and cooled into the cool air at 8 in the turbine. The cool air at 8 is then ducted to the air-conditioned rooms on ship. The seawater is heated in the sur-face heat exchanger, and flashed in a tank with a very low pressure. And the vapor from flash is condensed to freshwater in another tank.
Fig. 1. Representation on enthalpy–entropy coordi-nates of an open air-compression refrigeration system for air-conditioning and desalination on ship cooled
by seawater.
AC:Atomizing chamber C:Compressor SHE:Surface Heat exchanger T:
Turbine
Fig. 2. Circuit diagram of an open air-compression refrigeration system for air-conditioning and desalina-tion on ship cooled by seawater.
S. Hou et al. / Desalination 222 (2008) 646–655649
The freshwater injection before the axial compressor aims at decreasing both the temper-ature of the working fluid and the polytropic exponent in the compression process. Thus, we can save some compression work. This method has been used in a jet engine when a fighter plane speeds up. However, the difference is that what is injected in a jet engine is water, alcohol, etc. [21]. The water vapor in the compressed air can easily be extracted by a surface heat exchanger.With the same temperature, the humidity ratio of the saturated wet air at high pressure P 4 is only about P 3/P 4 of that at the pressure P 3. The method of using compressed air to acquire dry air has been used in some workshop in southern China. The system above differs from a conven-tional air-cycle system. There are many charac-ters in this air–vapor refrigeration circle.
Firstly, an axial compressor and a turbine are used in the above system. The characteristics of turbo-machines are large mass flow rate and high efficiency. And the other types of compressor and expander have none of the advantages above. Secondly, this refrigeration system intakes the precooled wet air with fine water droplet and some vapor is condensed during air-cooling from 4 to 7. The amount of the water extracted from high pressure wet air can reach 18–30g/kg (d.a.). And the amount of the latent heat dis-charged form vapor condensed, about 45–75kJ/kg (d.a.), exceeds the sensible heat from air,30–50kJ/kg (d.a.). For this reason, refrigeration load in this air–vapor refrigeration system depends on a combination of the sensible heat of air and the latent heat of vapor.
Lastly, the cool from the cooling seawater was used. Usually, it cannot be used.
3. Performance simulation 3.1. Wet air
The humidity ratio of wet air, d , is obtained from [26]
(1)
The enthalpy of wet air, h , is calculated from [26]
(2)The used relations for water vapor between saturation pressure and saturation temperature are
(3)or
(4)which are fitted from the data in AHRAE hand-book [26].
3.2. Axial compressor
During the compression process of wet air,the fine water droplet in the air may evaporate.Because the evaporation of water intakes heat,we can regard the ideal compression process of the wet air in the compressor as a polytropic process. Therefore, we can obtain the ideal work of the compressor per kilogram dry air, w c , from
(5)
in which, n is the polytropic exponent for the
compression process.
h t d t =++1006000125011805..(.)P t s s 133322exp
1853839622123286=×?+.(../.)t P s s 39622118538
ln 133********=??./(.(/.)).
650S. Hou et al. / Desalination 222 (2008) 646–655 The practical work consumed by the axial
compressor is w
c /h
c
, in which h
c
is the thermal
efficiency of the compressor.
3.3. Turbine
The saturated air with a pressure of P
7 and a
temperature of T
7 before the turbine has been
dehumidified in surface heat exchanger by cool-ing seawater. At point 7, the amount of vapor included in the saturated air is very small, about
P 3/P
7
of the mount included in saturated air at
P 3. Thus, the water condensed in air is fog. Nev-
ertheless, the expansion of the saturated air in the turbine cannot be regarded as an adiabatic expansion of an ideal gas. With the decrease of the wet air pressure in the turbine, the tempera-ture of the wet air decreases, and some heat is discharged during the condensation of some water vapor. The heat discharged may cause the increase in both the temperature of the turbine outlet and the work done in the expansion.
For this problem, we can imagine that no phase change exists and that there is some heat added to the wet air during the expansion pro-cess when we calculate the work done by the expansion process. According to the above assumption, this problem can be simplified to a problem of the polytropic expansion of an ideal gas. Consequently, we can obtain the ideal work
done by the expansion, w
t , through iteration,
and then obtain the real work generated by the turbine and the temperature of the turbine outlet.
3.4. Surface heat exchanger
Pinch technology is used in the analysis of heat exchange in the surface heat exchanger and the temperature difference at pinch point is 6°C. Pinch technology is a graphical method of iden-tifying technically and economically interesting energy efficiency measures. The minimum cooling and heating demands in the system can thereby be determined, together with the net heat for each temperature level.
The optimum mass flow rate ratio of cool water to dry air could be obtained from hot and cold curves according to pinch technology.
4. Performance
The heat rejected per kilogram dry air, q
1
, can be determined by the enthalpy difference between the inlet of the compressor and the out-let of the first surface heat exchanger by using the following formula:
(6)
The freshwater product rate per kilogram dry air, , can be determined by the following formula:
(7)
The refrigerating capacity per kilogram dry air, q
2
, can be determined by the enthalpy differ-ence between the inlet of the compressor and the outlet of the turbine by using the following formula:
(8)
The work consumed by the refrigeration cycle is calculated by
(9)
The COP of this refrigeration system is cal-culated by the following formulas. (The work consumed in cooling water system is not
included in .)
(10) q h h
146
=?
m
w
m d d q r
w381
=?+/
q h h
238
=?
w
m
S. Hou et al. / Desalination 222 (2008) 646–655651
5. Results
There are many factors that may influence the COP of t an open air–vapor compression refrigeration system for both air-conditioning and desalination on ship cooled by seawater.These include the pressure ratio of the axial compressor, P 4/P 3, the efficiencies of the axial compressor and turbine, the wet bulb tempera-ture of the atmosphere T wet and the cooling sea-water temperature. The freshwater product is rest on the heat rejected from the cooling the compressed air.
During simulation, the pressure ratio of axial compressor varied from 1.6 to 2.5, wet bulb temperature of the outdoor air from 20 to 30°C and the cooling water temperature are 15–27°C. There is 300 Pa pressure loss before the axial compressor, 300 Pa between the axial compres-sor and turbine, and 600 Pa after the turbine. Some encouraging results are illustrated in Figs. 3–8. The sensitivity of COP to efficiencies of the axial compressor and turbine is illustrated in Figs. 3 and 4. Lines in Fig. 3 are the COP lines of an open air-compression refrigeration system for air-conditioning and hot water cooled by cool water when T 7=30°C and efficiencies of the axial compressor and turbine are 90%, 88%,
86% and 80%, respectively. Lines in Fig.4 are the COP lines of an open air-compression refrig-eration system for air-conditioning and hot water cooled by cool water when T 7=25°C and effi-ciencies of the axial compressor and turbine are 90%, 88%, 86% and 80%, respectively. From Figs. 3 and 4, the efficiencies of the axial com-pressor and the turbine influence the COP heavily. The COP is higher when T 7 is lower. The COP to efficiencies of the axial com-pressor and turbine when P 4/P 3=2.2, h c =0.90and h t =0.90 is illustrated in Fig. 5. Fig. 5 gives the variation of COP with T 3 (T wet ) and T 7.
Although the sensitivity of COP to efficien-cies of the axial compressor and turbine, these circles are feasible. Firstly, this new turbo-machinery works near the design point, and effi-ciencies of axial compressor and turbine are very high at the design point, about 0.89–0.91.Secondly, the intake air is clean and without dust, therefore efficiencies of axial compressor and turbine will not drop greatly while working.Thirdly, there is no very complex combustion chamber and high-temperature turbine in the turbo-machinery. Consequently, it is much easier to accomplish than many people imagined. Lastly,efficiencies of axial compressor and turbine have
Fig. 3. The sensitivity of COP to efficiencies of the axial compressor and turbine when T 7=30°C.
Fig. 4. The sensitivity of COP to efficiencies of the axial compressor and turbine when T 7=25°C.
652S. Hou et al. / Desalination 222 (2008) 646–655 room for improvement with additional design
measures.
The simulations of an open air-compression
refrigeration system for air-conditioning and
desalination on ship cooled by seawater when
h c =0.90, h
t
=0.90, T
7
=30°C and P
4
/P
3
=2.2
are illustrated in Figs. 6–8. Fig. 6 gives the relations of the temperature after compressor,T
4
, the temperature before turbine, T
7
, and the temperature after turbine, T
8
to the temperature before compressor, T
3
(T
wet
). Fig. 7 gives the rela-tions of the refrigerating capacity per kilogram dry air, q
2
. The discharging heat per kilogram dry air, q
1
, and the work consumed by the refrig-eration system, w
m
, to the temperature before
Fig. 5. The COP to efficiencies of the axial compressor
and turbine when P
4/P
3
=2.2, h
c
=0.90 and h
t
=0.90.
Fig. 6. The simulated temperatures of an open air-com-
pression refrigeration system for air-conditioning and
desalination on ship cooled by seawater when h
c
=0.90,
h
t
=0.90, T
7
=30°C and P
4
/P
3
=2.2.
Fig. 7. The simulated q
1
, q
2
, w
m
of an open air-
compression refrigeration system for air-conditioning
and desalination on ship cooled by seawater when
h
c
=0.90, h
t
=0.90,T
7
=30°C and P
4
/P
3
=2.2.
Fig. 8. of an open air-compression refrigeration
system for air-conditioning and desalination on ship
cooled by seawater when h
c
=0.90, h
t
=0.90 and
P
4
/P
3
=2.2.
m
w
S. Hou et al. / Desalination 222 (2008) 646–655653
compressor, T 3 (T wet ). The relation of COP to the temperature before compressor, T 3 (T wet ) can be located in Fig. 4.
Fig. 8 gives of an open air-compression refrigeration system for air-conditioning and desalination on ship cooled by seawater when h c =0.90, h t =0.90 and P 4/P 3=2.2. From Fig. 8,the higher outdoor temperature, and the more freshwater product rate per kilogram dry air, . Fig. 9 is the pinch chart of wet air and cool-ing seawater in the surface heat exchanger when h c = 0.90, h t = 0.90 and P 4/P 3 = 2.2. In Fig. 9, T
4′and T 4 are the point 4 when T 3=25°C and 30°C,respectively. 6. Conclusions
This study shows the feasibility of an open air–vapor compression refrigeration system for both air-conditioning and desalination on ship cooled by seawater. The calculation results show
(1)The open air–vapor compression refrigera-tion system for both air-conditioning and desalination on ship cooled by seawater given in this paper could use the cool energy in cold seawater, which could not be used to
cool air directly. Also, the heat rejected by this system could be used for desalination.The freshwater could be obtained from both the dehumidification of wet air before the turbine and the flash and condensation of the cooling seawater.
(2)
H umid air is a perfect working fluid for refrigeration in central air-conditioning. (3)
To compare with air–vapor compression refrigeration system for air-conditioning cooled by circulating-water [23], this sys-tem is suitable to be employed on ship,where we could get cold seawater easily. (4)
The COP of this refrigeration system varies with the wet bulb temperature of the atmo-sphere. The higher the wet bulb temperature of the atmosphere, the higher COP of this refrigerating air-conditioning circle.
(5)
The COP of this refrigeration system rests mainly on h c and h t . The temperature of cold seawater will also affect it heavily, although the sensitivity of the COP to h c and h t , an open air–vapor compression refrigeration cycle for air-conditioning and desalination cooled by cold seawater is still feasible. (6)The freshwater product rate is mainly rest on the rejected heat while cooling the com-pressed wet air.
(7)
Pinch technology is a good method to ana-lyze the heat exchange of wet air-cooling.
Nomenclature B wet air pressure
Pa
d humidity ratio of wet air g/kg (d.a.) h enthalpy of wet air kJ/kg (d.a.)P pressur
e Pa t temperature °C
T temperature
K or °C T wet wet bulb temperature
kJ/kg (d.a.)q 1the heat rejected to outdoor air per kilogram dry air kJ/kg (d.a.)q 2
the refrigerating capacity per kilogram dry air
kJ/kg (d.a.)
m
w m w Fig. 9. Pinch chart in the surface heat exchanger when h c =0.90, h t =0.90 and P 4/P 3=2.2.
654S. Hou et al. / Desalination 222 (2008) 646–655
w
c ideal input work of a
compressor kJ/kg (d.a.)
w
t ideal output work of a
turbine kJ/kg (d.a.)
w
m practical work consumed
by the system kJ/kg (d.a.)
h c efficiency of a compressor
h t efficiency of a turbine
r latent heat of vaporization
of water kJ/kg
R gas constant kJ/kg k
n exponent
freshwater product rate
per kilogram dry air g/kg (d.a.)
Subscripts
d.a.dry air
vap.the water vapor in moist air
s saturated
w water
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2001, ASHRAE 1791 Tulie Circle, Atlanta, Georgia
30 329, USA.
Openair等离子处理技术在汽车工业中的应用 作者：德国Plasmatreat公司来源：AI汽车制造业 在众多的预处理方法中，常压等离子工艺在汽车工业中显示出了日益重要的作用。它不仅能够为塑料零部件提供极其洁净的表面，而且还可以提高表面的粘附能力，在应用多样性方面几乎不存在任何限制。和传统的处理方法相比，其经济性更好，并且对环境绝对没有任何负作用。 对于大多数塑料件的加工而言，为了确保塑料粘合面的粘合品质及其承载性能的长期稳定性，需要对材料表面进行正确的预处理，这已成为塑料件加工过程中的关键一步。正因如此，一种被称为“Openair常压等离子处理技术”的预处理工艺获得了越来越多的应用。 Openair常压等离子工艺使预处理工作更加简便、可靠，并且由于无需溶剂而更为环保。因此在汽车工业里，目前约有30多个不同的制程已经采用了该工艺：从汽车挡风玻璃粘合前预处理到汽车引擎控制器盒的封装，从冷藏卡车冷藏货柜的结构粘合到汽车车身部件的粘合等，Openair常压等离子工艺均显示出了其独有的技术优势。 图1 等离子体产生的原理，通过放电给气体施加更多的能量， 使物质从气态转变为等离子态 Openair常压等离子工艺基本原理 等离子体是指物质处于高能、非稳定的一种状态。通常，通过能量（比如加热）输入的方式，可以使物质从固态变为液态再到气态。等离子体就是在这一过程中再进一步，即通过放电将更多的能量注入物质中，电子获得更多动能后脱离其在原子中既有的轨道，从而产生自由电子、离子以及分子碎片，如图1所示。然而，由于这种物质状态不稳定，因此基本上不能在常 压下应用。
图 2 根据喷嘴的几何形状，在最宽50 mm 的处理范围内或者40 mm 的处理距离内都可获得有效的等离子体（图片来源于Plasmatreat 公司） 迄今为止，只有获得专利的Openair常压等离子工艺开创了这一新工艺应用的可能性：通过采用等离子喷枪，使在常压下产生的稳定的等离子体能够成功地应用于工业生产过程中，甚至还可以实现“在线处理”。一般，导入到等离子喷枪中籍以产生等离子的仅仅是空气和高电压，当然如果工艺需要也可以采用其它工艺气体。根据喷嘴的几何形状，可以在最大50 mm 宽度范围内或者40 mm 的距离范围内获得有效的等离子体，如图2 所示。通常，所形成的等离子体束还有一个独特的性质，即电中性，这极大地扩展了它的应用领域，并大大提升了操作便利性。发射出的等离子体温度取决于电源和等离子体源的配置，可以在300℃～1500℃之间变化，从而可以兼顾最佳处理效果和最高的处理效率。利用这种处理方式，在处理塑料表面时，典型的温度变化范围小于20 ℃。 冷藏车货柜的结构粘合 早在20世纪90年代，随着新一代车型的开发，Schmitz Cargobull公司就已将电中性常压等离子体的应用扩展到了一个新的领域。该公司计划将结构粘合作为冷却货柜装配的唯一方法，如图3所示。
鞋舌上标注说明：CM即厘米，为鞋的部长度;EUR即欧洲码，为中国人平时购鞋时所说的鞋码;US即美国码，UK即英国码也都是选购运动鞋时的一个参照。脚板窄者选鞋不会有太大影响，脚板宽或厚者需穿大一号甚至大二号的鞋! 鞋子尺码对照表 标准通用尺码对照表 男鞋尺码对照表(标准通用) 女鞋尺码对照表(标准通用)
Adidas 尺码对照表 Adidas 男鞋尺码对照表 欧洲码/EUR 39 40 40.5 41 42 42.5 43 44 44.5 45 46 46.5 47 厘米/CM 24 24.5 25 25.5 26 26.5 26.5 27 27.5 27.5 28 28.5 29 英国码/UK 6 6.5 7 7.5 8 8.5 9 9. 5 10 10.5 11 11.5 12 标准尺码(mm) 240 245 250 255 260 265 270 275 280 285 290 295 女式 欧洲码/EUR 36 36.5 37 38 38.5 39 40 40.5 41 42 42.5 厘米/CM 22 22.5 23 23.5 23.5 24 24.5 24.5 25 26 26.5 英国码/UK 3. 5 4 4. 5 5 5.5 6 6.5 7 7. 5 8 8.5 中性 欧洲码/EUR 36 36.5 37 38 38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 46 厘米/CM 22 22.5 23 23.5 23.5 24 24.5 24.5 25.5 26 26.5 26.5 27 27.5 27.5 28 英国码/UK 3. 5 4 4. 5 5 5.5 6 6.5 7 7.5 8 8.5 9 9. 5 10 10.5 11 Nike 尺码对照表 Nike 男鞋尺码对照表 欧洲码/EUR 38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 45.5 46 47 47.5 厘米/CM 24.5 24.5 25 25.5 26 26.5 27 27.5 28 28.5 29 29.5 30 30.5 31 美国码/US 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 12 12.5 13
JIG SAW 600W 曲线锯 600W
1. Blade holder(装刀处) 2. Adjustable foot (0-45 o)（底板） 3. Initial cutting switch（抬刀调节旋钮） 4. Guide speed control（调速开关） 5. Switch lock（开关锁钮） 6. Switch（开关按钮） 7. Cutting line laser indicator（激光口） Before you start using the tool please read thoroughly this operation manual. Keep this manual for future reference. 当您在开始使用机器前请先阅读说明书，请保留说明书以备随时查阅。 General safety precautions for using power tools. 使用电动工具的安全规范 NOTE. To reduce the risk of fire, electric shock or injury when using power tools, it is necessary to follow all applicable safety precautions particularly the ones listed below: 1.Keep work area clean and tidy.保持工作环境的整洁。 2.Do not use electric power tools in the environment exposed to humidity, steam or rain. Work place should be properly lit.请不要在潮湿的环境中或是雨天，阴暗 的地方使用电动工具。 3.Guard against electric shock. Prevent body contact with energized or grounded surfaces (pipes, radiators etc.). While operating the power tool always hold it by insulated parts (handles) to protect yourself against electric shock and protect drill, cutting wheel or milling cutter against contact with an energized conductor.避免 触电，防止身体接触机器导电部件，机器操作过程中请一直保持接触绝缘部 件，当机器运行时，请不要接触导轮，和锯条部分。 4.Keep children and visitors away.避免小孩碰及和使用。 5.Power tools should be stored in a dry location protected against dust and moisture. Keep them out of reach of children.电动工具需要存放在干燥的地方，并且注 意防潮，放在小孩触及不到的地方。 6.Do not use the tool for purposes it is not designed for.不要使用设计范围以外的 用途。 7.Dress properly. Do not wear loose clothing, jewellery or other items that can get within reach of rotating parts of the tool. Wear protective hair covering to contain
鞋码对照表,中国/美国/国际鞋码对照表 鞋码，通常也称鞋号，是用来衡量人类脚的形状以便配鞋的标准单位系统。目前世界各国采用的鞋码并不一致，但一般都包含长、宽两个测量。长度是指穿者脚的长度，也可以是制造者的鞋楦长。即使在同一个国家/地区，不同人群和不同用途的鞋，例如儿童、运动鞋，也有不同的鞋码定义。下面是尺码对照表，可以帮你解决如何挑选正确的码数；经过量度脚长与脚宽，让你能够挑选到合适的鞋子。 国际标准鞋号表示的是脚长的毫米数。 中国标准采用毫米数或厘米数。如：245是毫米数，24 1/2是厘米数，表示一样的尺码。 换算公式： 厘米数×2－10=欧制（欧制+10）÷2=厘米数 厘米数－18+=美制美制+18－=厘米数 厘米数－18－=英制英制+18+=厘米数 （欧码+10）×5=中国鞋号，如欧码35的鞋，对应的中国鞋号为225；欧码37对应的中国鞋号为235。 鞋号换算表（单位：毫米）34号——22035号——22536号——23037号——23538号——24039号——24540号——25041号——25542号——26043号——26544号——27045号——275。 男人鞋尺码对照表： 女人鞋尺码对照表：
儿童鞋尺码对照表： 国际(成年人)女鞋码尺寸对照表：
国际(成年人)男子鞋码尺寸对照表：
标准通用尺码对照表 男鞋尺码对照表（标准通用） 尺码 39 40 41 42 43 44 45 46 47 脚长(mm) 美国码 7 8 9 10 日本码 国际码 245 250 255 260 265 270 275 280 285 女鞋尺码对照表（标准通用） 尺码 35 36 37 38 39 40 41 42 脚长（mm） 美国码 5 6 7 8 日本码 国际码 225 230 235 240 245 250 255 260 Adidas 尺码对照表 Adidas 男鞋尺码对照表 中国码 38 2/3 39 1/3 40 40 2/3 41 1/3 42 42 2/3 43 1/3 44 44 2/3 45 1/3 46 美国码 6 7 8 9 10 11 英国码 6 7 8 9 10 11 标准尺码（mm） 240 245 250 255 260 265 270 275 280 285 290 295 Nike 尺码对照表 Nike 男鞋尺码对照表 中国码 39 40 41 42 43 44 45 美国码 6 7 8 9 10 11
《高职高专教育英语课程教学基本要求》所列常用短语 A be able to do sth. 能，会along with 和…一起，除了…之外 be about to do sth. 刚要，即将not only…but also 不但而且 above all 首先，尤其是amount to 总计，等于 have access to 有…的机会，有…权利be angry with 生（某人的）气 by accident 偶然one after another 一个接一个地，接连地according to 根据。按照one another 相互 on account of 因为，由于be anxious about 为…而忧虑 take into account 把…考虑进去any but 除….之外人和事（物），绝非accuse of 指控，控告apart from 除…之外 be accustomed to 习惯于appeal to 吸引，呼吁，上诉 adapt to 适应apply to 应用 add to / add… to 为…增添，增加apply for申请 add up to 合计达as…as 象…一样 in addition 另外，加之as for / to 至于，关于 in addition to 除…之外，（还））as if / as though 好像，仿佛 adjust to / adjust …to 适应于as soon as …possible 尽快 in advance 预先，提前as / so long as 只要，如果 gain / have an advantage over 胜过，优于as well 也，又 take advantage of 利用，趁….之机as well as 也，既…又 be afraid of 害怕aside from …暂且不谈，除…之外 again and again 反复地，再三地ask for 要，要求 once again 再一次assign sth. to sb. 分配，布置 aim at 瞄准associate with / associate … with 联系，交往 in the open air 在户外，在野外attend to 专心于，致力于 on the air (用无线电、电视)播送pay attention to 注意 above all 首先，尤其是on (the / an) average 平均，通常 after all 毕竟，终究be aware of 察觉到，了解 all in all 大体而言right away 立刻，马上 all but 几乎，差不多，除了…都 all over 到处，遍及 all right 良好的，对的/ （口语）行，可以 at all （用于否定句）丝毫（不），一点（不） in all 总共，合计 B back and forth 来回地，反复地bear on / upon 压迫，依靠；与…有关 back up 倒退，支持，备份because of…因为，由于 be bad for 对…有害的before long 不久以后 go bad 变坏，坏掉on behalf of 代表，为了 keep one’s balance 保持平衡begin with 从…开始，以…为起点 be based on / upon 把…建立在…基础上believe in 相信，信任 on the basis of 根据belong to 属于 bear…in mind 记住benefit from 有益于，得益 at best 充其量，至多build up 逐步建立，增长，集聚，增强…的体力
鞋舌上标注说明：CM即厘米，为鞋的内部长度;EUR即欧洲码，为中国人平时购鞋时所说的鞋码;US即美国码，UK即英国码也都是选购运动鞋时的一个参照。脚板窄者选鞋不会有太大影响，脚板宽或厚者需穿大一号甚至大二号的鞋! 鞋子尺码对照表 标准通用尺码对照表 男鞋尺码对照表(标准通用) 女鞋尺码对照表(标准通用)
Adidas 尺码对照表Adidas 男鞋尺码对照表 欧洲码/EUR 3 9 40 40. 5 41 4 2 42. 5 43 44 44. 5 45 4 6 46. 5 4 7 厘米/CM 2 4 24. 5 25 25. 5 2 6 26. 5 26. 5 27 27. 5 27. 5 2 8 28. 5 2 9 英国码/UK 6 6.5 7 7.5 8 8.5 9 9. 5 10 10. 5 1 1 11. 5 1 2 标准尺码(mm) 240 245 250 255 260 265 270 275 280 285 290 295 女式 欧洲码 /EUR 36 36. 5 37 38 38. 5 3 9 40 40. 5 41 4 2 42. 5 厘米/CM 22 22. 5 23 23. 5 23. 5 2 4 24. 5 24. 5 25 2 6 26. 5
英国码/UK 3. 5 4 4. 5 5 5.5 6 6.5 7 7. 5 8 8.5 中性欧洲码 /EUR 36 36. 5 37 38 38. 5 3 9 40 40. 5 41 4 2 42. 5 43 44 44. 5 45 4 6 厘米/CM 22 22. 5 23 23. 5 23. 5 2 4 24. 5 24. 5 25. 5 2 6 26. 5 26. 5 27 27. 5 27. 5 2 8 英国码/UK 3. 5 4 4. 5 5 5.5 6 6.5 7 7.5 8 8.5 9 9. 5 10 10. 5 1 1 Nike 尺码对照表Nike 男鞋尺码对照表 欧洲码/EUR 38. 5 39 4 40. 5 4 1 42 42. 5 43 4 4 44. 5 4 5 45. 5 4 6 47 47. 5 厘米/CM 24. 5 24. 5 2 5 25. 5 2 6 26. 5 27 27. 5 2 8 28. 5 2 9 29. 5 3 30. 5 31 美国码/US 6 6.5 7 7.5 8 8.5 9 9.5 1 0 10. 5 1 1 11. 5 1 2 12. 5 13 标准尺码(mm) 240 245 250 255 260 265 270 275 280 285 290 Nike 女鞋尺码对照表 欧洲码 /EUR 35 35. 5 36 36. 5 37. 5 3 8 38. 5 3 9 40 40. 5 41 4 2 43
★鞋子尺码对照表大全(标准通用)★美国码★日本码★国际码★英国码★ 鞋子尺码对照表 标准通用尺码对照表 男鞋尺码对照表（标准通用） 尺码39 40 41 42 43 44 45 46 47 脚长(mm)23.6-24 24.1-245 24.6-250 25.1-255 25.6-260 26.1-265 26.6-270 27.1-275 27.6-280 美国码 6.5 7 7.5 8 8.5 9 9.5 10 10.5 日本码24.5 25.0 25.5 26.0 26.5 27.0 27.5 28.0 28.5 国际码245 250 255 260 265 270 275 280 285 女鞋尺码对照表（标准通用） 尺码35 36 37 38 39 40 41 42 脚长（mm）22.1-225 22.6-230 23.1-235 23.6-240 24.1-245 24.6-250 25.1-255 25.6-260 美国码5 5.5 6 6.5 7 7.5 8 8.5 日本码22.5 23.0 23.5 24.0 24.5 25.0 25.5 26.0 国际码225 230 235 240 245 250 255 260 Adidas 尺码对照表 Adidas 男鞋尺码对照表 中国码38 2/3 39 1/3 40 40 2/3 41 1/3 42 42 2/3 43 1/3 44 44 2/3 45 1/3 46 美国码6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 英国码5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 标准尺码（mm）240 245 250 255 260 265 270 275 280 285 290 295 Nike 尺码对照表 Nike 男鞋尺码对照表 中国码38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 美国码6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 英国码5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 标准尺码（mm）240 245 250 255 260 265 270 275 280 285 290 Nike 女鞋尺码对照表 中国码35 35.5 36 36.5 37.5 38 38.5 39 40 40.5 41 美国码4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 英国码2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 标准尺码（mm）220 220 225 230 235 240 245 250 255 260 265 Reebok 尺码对照表 Reebok 男鞋尺码对照表
高中英语会考说明词语翻译 At the age of 在…年龄 At the end of 在…结尾 At the head of 在…前面 At the mercy of 任由…摆布: 在…的掌握中 At the moment 在…时候 At the same time 与…同时,一齐 At times =now and then 间或，时常 At work 在工作，在上班 Be addicted to 沉溺于，上瘾 Be afraid of 担心，害怕 Be amazed at 对…感到害怕 Be angry with sb. 生…的气 Be aware of 知道，了解，意识到 Be busy doing sth. 忙于… Be busy with sth. 忙于… Be famous for 因…而著名=be known for Be fit for 适合于 Be fond of 喜欢 Be full of 充满 Be good at something \ doing 善于 Be late for 做…迟到 Be like 用…做的 Be made up of 由…构成 Be on good terms (with sb.) 与…关系良好 Be satisfied with 对…满意=be pleased with =be content with Be used to sth / doing 习惯于 Because of 因为 Before long 不久，没过多长时间 Begin with=start with 以…方式开始 Believe in 信赖，信仰… Belong to 归于，属于 Benefit from 从中获利（益） Both…and……和…:不仅…而且 Break away from 脱离，与…分手 Break down 分解；(人)病倒，（机器）坏了，（车）抛锚 Break out （疾病，战争，洪水，地震等）爆发（没有被动形势） Bring …back to life 使…复活；使…苏醒；使…充满生机 Bring in 带来，挣（钱），引进 Bring (sb.) back 把…带回来，使恢复 Bring up 把…抬高，抚养（常用被动形势） Burn down 烧毁（房屋，城镇） Burst into sth. 突然大声地（哭，笑等）burst into tears / laughter By bus/plane/ship/air/sea 乘…交通工具 By mistake 偶然，无意地 By the side of 在…边上 By the time 到…时候
男鞋尺码标准对照表：（日本的单位为cm） 欧洲（EUROPE）39 40 40.5 41 42 42.5 43 44 44.5 45 美国（US）6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 英国（UK）6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 日本（JAPAN）24.5 25 25.5 26 26.5 27 27.5 28 28.5 29 台湾（TAIWAN）69 70 71 72 73 74 75 76 77 78 中国码39 39.5 40 41 42 42.5 43 43.5 44 45 女鞋尺码标准对照表：（日本的单位为cm） 欧洲(EUROPE）34 34.5 35 35.5 36 36.5 37 37.5 38 38.5 39 39.5 40 美国（US）4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 英国（UK）2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 日本（JAPAN）21 21.5 22 22.5 23 23.5 24 24.5 25 25.5 26 26.5 27 台湾（TAIWAN) 64 65 66 67 68 69 70 71 72 73 74 75 76 中国码34 35 36 37 37.5 38 39 39.5 国际鞋码换算器”告诉大家，希望对大家有所帮助！！！ http://www.chinashoes.ru/cn/tool/size/size.html 另外还有对照表：
美欧陆鞋码对照表 女鞋尺码表 欧 35.5 36 36.5 37 38 39 39.5 40 41 42 42.5 43 44 44.5 45 46 47 码 英 3 3.5 4 4. 5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 11 12 国 码 美 国 5 5.5 6 6.5 7 7.5 8 8.5 9 10 10.5 11 11.5 12 12.5 13 13.5 码 男鞋尺码表 欧码38.5 39 40 40.5 41 41.5 42 43 43.5 44 45 45.5 46 47 48 英国码 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 12 13 美国码 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 12 13 14 童鞋尺码表 欧码20.5 21 22 23 24 24.5 25 26 27 28 29 30 31 31.5 32 33 美国 8.5 9 9.5 10 10.5 11 11.5 12 12.5 13 13.5 1 1.5 2 2.5 3 码 27码=腰围1尺9/63CM、裤长107CM、臀围98CM、大腿50CM、裤腿41CM、立裆29CM 28码=腰围2尺/67CM、裤长107CM、臀围100CM、大腿52CM、裤腿41CM、立裆30CM 29码=腰围2尺1/70CM、裤长107CM、臀围102CM、大腿54CM、裤腿42CM、立裆31CM 30码=腰围2尺2/73CM、裤长107CM、臀围104CM、大腿56CM、裤腿42CM、立裆32CM 31码=腰围2尺3/77CM、裤长107CM、臀围106CM、大腿58CM、裤腿42CM、立裆32CM 32码=腰围2尺4/80CM、裤长107CM、臀围108CM、大腿60CM、裤腿44CM、立裆33CM 33码=腰围2尺5/83CM、裤长107CM、臀围110CM、大腿62CM、裤腿44CM、立裆34CM 34码=腰围2尺6/87CM、裤长110CM、臀围112CM、大腿64CM、裤腿44CM、立裆35CM 36码=腰围2尺7/90CM、裤长110CM、臀围118CM、大腿65CM、裤腿46CM、立裆36CM
an active vertical urban living area Department of ARCHITECTURE Bangkok, Thailand 2016
在不断进化。曼谷城市密度高，室外空间有限，百姓 急需新的适应热带气候的室外生活空间。 For Bangkok, or any other modern-day cosmopolitan cities, living conditions and spatial form continue to evolve. Bangkokians are now yearning for new possibilities of outdoor living space that can effectively answer to the tropical heat and its dense living condition where there is not much space for the outdoor. The Commons是一个位于城市中心的小商业项目， 旨在创造一个活跃而舒适的室外空间，让人们可以在 一年四季享受其中。 “The Commons”, a small retail development in the city center, is an attempt to create a new active outdoor space where people can comfortably enjoy it at anytime of the year. 建筑外观external view of the building
各种阀门[VALVE]的基本介绍 阀门是国民经济建设中使用极为广泛的一种机械产品。阀门在石油、天然气、煤炭、冶金、和矿石的开采、提炼加工和管道输送系统中；阀门在石油化工、化工产品，医药，和食品生产系统中；阀门在水电、火电和核电的电力生产系统中；阀门在城建的给排水、供热和供气系统中；阀门在冶金生产系统中；阀门在船舶、车辆、飞机、航天以及各种运动机械的使用流体系统中；阀门在国防生产以及新技术领域里；阀门在农业排灌系统中都有大量的需求。 Valve is a widely used mechanical product in each country's economy. You can find valves commonly used in the following fields like oil, nature gas, coal, metallurgy, mining, refinery, pipe transportation, petrochemical, chemical, pharmacy, food production, power plant, water supply / drainage, heat supply, air supply, marine, vehicle, airplane, spacecraft, military, new tech, irrigation and many other flowing systems. 阀门分自动阀门与驱动阀门。自动阀门（如安全阀、减压阀、蒸汽疏水阀、止回阀）是靠装置或管道本身的介质压力的变化达到启闭目的的。驱动阀门（闸阀、截止阀、球阀、蝶阀等）是靠驱动装置（手动、电动、液动、气动等）驱动控制装置或管道中介质的压力、流量和方向。由于介质的压力、温度、流量和物理化学性质的不同，对装置和管道系统的控制要求和使用要求也不同，所以阀门的种类规格非常多。剧不完全统计，我国的阀门产品品种已达四千多个型号，近四万个规格，阀门在经济生活中起着非常大的作用。 There are self-driven valves and operated valves. self-driven valves( like safety valve, relief valve, steam trap, check valve ) are functioning by utilizing its mechanical design or the pressure, direction of its flow medium.operated valve( like gate valve, globe valve, ball valve, butterfly valve ) is fuctioning by actuator( manual, electric, hydraulic, pneumatic etc. ) or the pressure , flow direction of its medium. due to the differences of pressure, temperature, flow, and physical-chemical character of its medium , there are different requirements in designing and applying the pipeline system.therefore there are numerous types of valve.according to an unofficial statistics, there are more than four thousand types of valve with approximately forty thousand specifications in China. Obviously, valve is an important element in the social economy. 电磁阀[SOLENOID VALVE] 电磁阀是用来控制流体的自动化基础元件，属于执行器；并不限于液压，气动。电磁阀用于控制液压流动方向，工厂的机械装置一般都由液压钢控制，所以就会用到电磁阀。而通常意义上，国内电磁阀厂家也并不以液压电磁阀为主打，一般多生产二位二通气液用电磁阀。 Solenoid valve is a basic component in automatic flow control, it is actuator but not limited to hydraulic, pneumatic. solenoid valve is mainly used to control the direction of hydraulic flow, machines in plant are usually controled by hydraulic cylinder and thus the solenoid valve is applyed. generally , solenoid valve manufacturers in China not only produce hydraulic solenoid valve, they mainly manufacturer hydraulic-pneumatic combined two way solenoid valve. 电磁阀的工作原理，电磁阀里有密闭的腔，在的不同位置开有通孔，每个孔都通向不同的油管，腔
★鞋子尺码对照表大全(标准通用)★美国码★日本 码★国际码★英国码★ 鞋子尺码对照表 标准通用尺码对照表 男鞋尺码对照表（标准通用） 尺码 39 40 41 42 43 44 45 46 47 脚长(mm)23.6-24 24.1-245 24.6-250 25.1-255 25.6-260 26.1-265 26.6-270 27.1-275 27.6-280 美国码 6.5 7 7.5 8 8.5 9 9.5 10 10.5 日本码 24.5 25.0 25.5 26.0 26.5 27.0 27.5 28.0 28.5 国际码 245 250 255 260 265 270 275 280 285 女鞋尺码对照表（标准通用） 尺码 35 36 37 38 39 40 41 42 脚长（mm） 22.1-225 22.6-230 23.1-235 23.6-240 24.1-245 24.6-250 25.1-255 25.6-260 美国码 5 5.5 6 6.5 7 7.5 8 8.5 日本码 22.5 23.0 23.5 24.0 24.5 25.0 25.5 26.0 国际码 225 230 235 240 245 250 255 260 Adidas 尺码对照表 Adidas 男鞋尺码对照表 中国码 38 2/3 39 1/3 40 40 2/3 41 1/3 42 42 2/3 43 1/3 44 44 2/3 45 1/3 46 美国码 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 英国码 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 标准尺码（mm） 240 245 250 255 260 265 270 275 280 285 290 295 Nike 尺码对照表 Nike 男鞋尺码对照表 中国码 38.5 39 40 40.5 41 42 42.5 43 44 44.5 45 美国码 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 英国码 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 标准尺码（mm） 240 245 250 255 260 265 270 275 280 285 290 Nike 女鞋尺码对照表 中国码 35 35.5 36 36.5 37.5 38 38.5 39 40 40.5 41 美国码 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 英国码 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 标准尺码（mm） 220 220 225 230 235 240 245 250 255 260 265
西湖英文介绍 West Lake or Xī Hú is a famous fresh water lake located in the historic area of Hangzhou, the capital of Zhejiang province in eastern China. It evolved from a shallow bay through which the Qiantang River flowed into the East China Sea. In the ancient times it was called Wulin Waters, Golden Buffalo Lake, Qiantang Lake and Xizi Lake. 西湖是座落在历史悠久的中国东部浙江省会城市杭州的著名的一个淡水湖泊，是由古代钱塘江流入东海前的一个浅海湾演变而成的。古称西湖为“武林水” 又称“金牛湖”、“钱塘湖”、“西子湖”等。 The name of West Lake was fixed as early as the Tang Dynasty (618-907). In the Song Dynasty (960-1279), the Chinese renowned(著名)poet Su Dongpo wrote a poem to praise the West Lake and compared it to Xizi, a Chinese legendary beauty. Since then, the West Lake has another elegant name Xizi Lake. And as it lies in the west of Hangzhou, it is usually called the West Lake. 西湖的名字早在唐朝(618-907)就固定下来。在宋代 (960-1279 年)，中国著名诗人苏东坡写的一首诗来赞美西湖，把它和中国传说中的美丽西子相比。自那时以来，西湖有另一种优雅的名字西子湖。并且由于它位于杭州市西部，它通常称为西湖。 West Lake covers an area of 6.38 square kilometers. The average depth is 2.27meters with deepest being 5 meters. Three sides of the lake are surrounded by verdant（翠绿的）mountains and one side the prosperous（繁荣的）city. After a large scale reconstruction（重建）, the current West Lake has recovered the panorama（全景）over 300 years before when it reached the most prosperous period in history。 西湖水域面积为6.38平方公里 水深平均2.27米 最深处有5米。西湖三面环山，一面濒城。西湖大规模重建后，目前已恢复全景超过300年之前，它到达最繁华的历史时期。 Centering around the West Lake, the scenic area is a national scenic area with a total cover of 59 square kilometers. There are over 60 Chinese national, provincial and municipal cultural relic protection sites and over 100 scenic areas. The main attractions include: Ten scenes of the West Lake, Ten New Scenes of the West Lake; Lingyin Temple, General Yuefei’ Temple and Pagoda of Six Harmonies and so on. 以西湖为核心的西湖风景名胜区总面积59平方公里，是中国国家级风景名胜区。区内有国家级、省级、市级文物保护单位60多处和风景名胜100余处。其中主要有“西湖十景”、“新西湖十景”有灵隐寺、岳王庙、六和塔等等。 The lake is divided into 5 parts by the causeways of Sū Dī (苏堤), Bái Dī (白堤), and Yánggōng Dī (杨公堤). There are numerous temples, pagodas, gardens, and artificial islands within the lake.With ripples on the water’s surface and thickly-wooded hills dotted by exquisite pavilions on its four sides, the West Lake is one of China’s best known scenic spots.