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NarrowBody aircraft - pneumatic system supplies air to Air Condition System

NarrowBody aircraft - pneumatic system supplies air  to Air Condition System
NarrowBody aircraft - pneumatic system supplies air  to Air Condition System

21 AIR CONDITIONING SYSTEM PRESENTATION BASIC AIR CONDITIONING SYSTEM INTRODUCTION

The pneumatic system supplies air to each pack. The packs are responsible

for BASIC temperature regulation.

Temperature regulated pack discharge air is sent to the mixer unit.

At the mixer unit, the air is mixed with air re-circulated from the main cabin. This reduces the overall bleed demand and saves fuel.

From the mixer, the air is distributed to the cockpit and the forward and

aft cabin zones.

Some of the air from the pneumatic system is used for the OPTIMIZED temperature regulation system. This hot air is mixed with the air from

the mixer to adjust the temperature in each zone independently.

The air is distributed throughout the cabin and finally, discharged overboard through the outflow valve to maintain pressurization.

21 AIR CONDITIONING SYSTEM PRESENTATION PACK INTRODUCTION

The Single Aisle family is equipped with two air conditioning packs located in the wing root area forward of the landing gear bay. The packs supply dry air to the cabin for air conditioning, ventilation and pressurization.

The main component of each pack assembly is the Air Cycle Machine.

Hot air from the pneumatic system is supplied to the pack through the pack Flow Control Valve (FCV). The FCV adjusts the flow rate through the pack and is the pack shut-off valve.

The pack temperature control system controls the pack outlet temperature and sets its maximum and minimum limits. The system includes two

Pack Controllers (PCs). Each PC controls one pack and has two computers, one primary and one electrically independent secondary computer. When the primary computer is operational, the system is fully functional. If the primary fails, some functions are lost as the secondary computer takes control.

During normal operation, the Zone Controller (ZC) sends the required pack outlet temperature to both PCs. To control the pack outlet temperature, the PC modulates the BYPASS V ALVE and the RAM-AIR INLET doors. For maximum cooling, the ram-air doors are fully open

and the bypass valve is fully closed. For maximum heating, the ram-air doors are nearly closed and the bypass valve is fully open. During takeoff and landing, the ram air inlet doors will be driven fully closed to stop the ingestion of foreign matter.

21 AIR CONDITIONING SYSTEM PRESENTATION PACK INTRODUCTION (continued)

ENHANCED

The ZCs and PCs are replaced by two Air Conditioning System

Controllers (ACSC) 1 and 2. ACSC 1 sends the pack outlet

temperature demand to pack 1. Air Conditioning System Controller

2 sends the pack outlet temperature demand to pack 2. To control the

pack outlet temperature, the Air Conditioning System Controller

modulates the BYPASS V ALVE and the RAM-AIR INLET doors.

For maximum cooling, the ram-air doors are fully open and the bypass valve is fully closed. For maximum heating, the ram-air doors are

nearly closed and the bypass valve is fully open. During takeoff and

landing, the ram air inlet doors will be driven fully closed to stop the ingestion of foreign matter.

21 AIR CONDITIONING SYSTEM PRESENTATION ZONE TEMPERATURE REGULATION SYSTEM INTRODUCTION

The packs supply the mixer unit. Three separate aircraft zones are supplied from the mixer unit:

- cockpit,

- forward cabin,

- aft cabin.

Two cabin recirculation fans are installed to reduce the bleed air demand and therefore save fuel. These fans establish a recirculation flow of air from the cabin zones to the mixer unit. In normal operation, there are no ECAM indications associated with the cabin fans.

The ZC controls and monitors the temperature regulation system for the cabin zones. On the overhead AIR COND panel, the flight crew selects

the desired individual compartment temperature.

The hot air system for cabin temperature control has a hot air valve and trim air valves controlled by the ZC. The ZC compares the demand to

the actual temperature in each zone.

The ZC then sends the pack outlet temperature demand to both PCs to satisfy the coldest demand.

For the zones, which require warmer temperature, the ZC signals the TRIM V ALVES to open. Hot air mixes with the pack discharge air and

the temperature increases. In the case of any duct overheat, the hot air valve and the trim air valves will automatically close to isolate the system. The system can be reset when the overheat disappears.

21 AIR CONDITIONING SYSTEM PRESENTATION ZONE TEMPERATURE REGULATION SYSTEM INTRODUCTION (continued)

ENHANCED

The Air Conditioning System Controllers (ACSC) control and monitor the temperature regulation system for the cabin zones. On the overhead AIR COND panel, the flight crew selects the desired individual

compartment temperature. The Air Conditioning System Controller

compares the demand to the actual temperature in each zone. Air

Conditioning System Controller 1 monitors the temperature of the

flight deck zone and sends the pack outlet temperature demand to

pack 1. Air Conditioning System Controller 2 monitors the temperature of the forward and aft cabins and sends the pack outlet temperature

demand to pack 2.

The trim air Pressure Relief Valve (PRV) and the trim air valves are

controlled by the Air Conditioning System Controllers. In the case of any duct overheat, the Trim air PRV and the trim air valves will

automatically close to isolate the system. The system can be reset

when the overheat disappears.

21 AIR CONDITIONING SYSTEM PRESENTATION CONTROL AND INDICATING

This section will highlight the control panels and indications for the air conditioning system.

CONTROL PANELS

On the overhead panel, the AIR COND panel is used by the pilot to

control the air conditioning system. This panel contains the PACK

switches, the zone temperature selectors, the PACK FLOW control,

and the HOT AIR control switch.

On the overhead, the VENTILATION panel contains the CAB FANS pushbutton switch. The switch is used to select the recirculation fans OFF.

21 AIR CONDITIONING SYSTEM PRESENTATION CONTROL AND INDICATING (continued)

ECAM PAGES

Basic temperature regulation is accomplished by the packs. Pack

parameters, such as pack flow and bypass valve position are found

on the upper section of the ECAM BLEED page.

The ECAM AIR COND page contains the optimized temperature

regulation parameters, such as duct temperature, zone temperature

and trim air system indications.

The ECAM CRUISE page also contains zone temperature indications.

This Page Intentionally Left Blank

21 AIR CONDITIONING SYSTEM PRESENTATION COMPONENT LOCATION

The left and right packs are located in the air conditioning bay. The air conditioning bay is located in the unpressurized belly fairing forward of the wheel well on the lower fuselage. The belly fairing has inlets for pack and compartment cooling.

The packs supply air to the mixer unit. The mixer unit is installed at the rear of the forward cargo compartment. It mixes air from the packs and

re-circulated air from the cabin prior to distribution to each zone.

21 AIR CONDITIONING SYSTEM PRESENTATION MAINTENANCE/TEST FACILITIES

The ZC is the interface between the PCs and the Centralized Fault Display Interface Unit (CFDIU) for test purposes and fault reporting. The ZC test

on the Multipurpose Control and Display Units (MCDUs) initiates a complete air conditioning test including the packs.

The ACSC are connected to the CFDIU for test purposes and fault reporting, available on the MCDU.

(易错题精选)初中英语词汇辨析的单元汇编含答案解析

一、选择题 1.I’d like to________the mall because it’s crowded and noisy. A.visit B.hang out C.walk D.go off 2.That path ________ directly to my house.You won't miss it. A.leads B.forms C.repairs D.controls 3.I don’t want to go. __________, I am too tired. A.However B.And C.Besides D.But 4.Some animals carry seeds from one place to another, ________ plants can spread to new places. A.so B.or C.but D.for 5.When I as well as my cousins __________ as a volunteer in Beijing, I saw the Water Cube twice. A.were treated B.treated C.was served D.served 6.He is wearing his sunglasses to himself from the strong sunlight. A.prevent B.stop C.keep D.protect 7.When you are________, you should listen to music to cheer you up. A.shy B.afraid C.strict D.down 8.Mr. Smith gave us some________on how to improve our speaking skills. A.advice B.news C.knowledge D.information 9.World Book Day takes place ________ April 23rd every year. A.at B.in C.on 10.More and more people have realized that clear waters and green mountains are as ________ as mountain of gold and silver. A.central B.harmful C.valuable D.careful 11.We loved the food so much, ________the fish dishes. A.special B.especial C.specially D.especially 12.—Oh, my God! I have ________ five pounds after the Spring Festival. —All of the girls want to lose weight, but easier said than done. A.given up B.put on C.got on D.grown up 13.—What do you think of the performance today? —Great! ________ but a musical genius could perform so successfully. A.All B.None C.Anybody D.Everybody 14.He ________ his homework________the morning of Sunday. A.doesn’t do; on B.doesn’t do; in C.doesn’t; on 15.Maria ________ speaks Chinese because she doesn’t know much Chinese. A.seldom B.always C.often D.usually 16.In 2018, trade between China and Hungary rose by 7.5 percent, and recently on Friday companies from China and Hungary________ several cooperation (合作) agreements under the

螺纹通止规

螺纹通止规 定是:螺纹止规进入螺纹不能超过2.5圈,一般的要实际不得超过2圈,并且用得力度不能大,我们的经验是用拇指和食指轻轻夹持螺纹规以刚好能转动螺纹规的力度为准.力大了就相当于在使用丝锥或牙板了,那样规就用不了几次了. 螺纹通止规 螺纹通止规是适用于标准规定型号的灯头作为灯用附件电光源产品时候的设计和生产、检验的工具设备。 用途 一般用于检验螺纹灯头或灯座的尺寸是否符合标准要求,分别检验螺纹灯头的通规和止规尺寸或灯座的通规或止规尺寸。 工作原理 具体检验要求及介绍详见中国人民国国家标准:GB/T1483.1-2008或 IEC60061-3:2004标准规定容。 操作方法 具体检验要求及介绍详见中国人民国国家标准:GB/T1483.1-2008或 IEC60061-3:2004标准规定容。 通止规

通止规,是量规的一种。作为度量标准,用于大批量的检验产品。 通止规是量具的一种,在实际生产批量的产品若采取用计量量具(如游标卡尺,千分表等有刻度的量具)逐个测量很费事.我们知道合格的产品是有一个度量围的.在这个围的都合格,所以人们便采取通规和止规来测量. 通止规种类 (一)对统一英制螺纹,外螺纹有三种螺纹等级:1A、2A和3A级,螺纹有三种等级:1B、2B和3B级,全部都是间隙配合。等级数字越高,配合越紧。在英制螺纹中,偏差仅规定1A和2A级,3A级的偏差为零,而且1A和2A级的等级偏差是相等的等级数目越大公差越小,如图所示:1B 2B 3B 螺纹基本中径3A 外螺纹2A 1A 1、1A和1B级,非常松的公差等级,其适用于外螺纹的允差配合。 2、2A和2B级,是英制系列机械紧固件规定最通用的螺纹公差等级。 3、3A和3B级,旋合形成最紧的配合,适用于公差紧的紧固件,用于安全性的关键设计。 4、对外螺纹来说,1A和2A级有一个配合公差,3A级没有。1A级公差比2A级公差大50,比3A级大75,对螺纹来说,2B级公差比2A公差大30。1B级比2B级大50,比3B级大75。 (二)公制螺纹,外螺纹有三种螺纹等级:4h、6h和6g,螺纹有三种螺纹等级:5H、6 H、7H。(日标螺纹精度等级分为I、II、III三级,通常状况下为II级)在公制螺纹中,H 和h的基本偏差为零。G的基本偏差为正值,e、f和g的基本偏差为负值。如图所示:公差G H 螺纹偏差基本中径外螺纹f g h e 1、H是螺纹常用的公差带位置,一般不用作表面镀层,或用极薄的磷化层。G位置基本偏差用于特殊场合,如较厚的镀层,一般很少用。 2、g常用来镀6-9um的薄镀层,如产品图纸要6h的螺栓,其镀前螺纹采用6g的公差带。 3、螺纹配合最好组合成H/g、H/h或G/h,对于螺栓、螺母等精制紧固件螺纹,标准推荐采用6H/6g的配合。 (三)螺纹标记M10×1–5g 6g M10×1–6H 顶径公差代号中径和顶径公差代号(相同)中径公差代号。 通止规是两个量具分为通规和止规.举个例子:M6-7h的螺纹通止规一头为通规(T)如果能顺利旋进被测螺纹孔则为合格,反之不合格需返工(也就是孔小了).然后用止规(Z)如果能顺利旋进被测螺纹孔2.5圈或以上则为不合格反之合格.且此时不合格的螺纹孔应报废,不能进行返工了.其中2.5圈为国家标准,若是出口件最多只能进1.5圈(国际标准).总之通规过止规不过为合格,通规止规都不过或通规止规都过则为不合格。

boring 令人厌烦的

boring 令人厌烦的,乏味的,无聊的 tedious 乏味的,单调的,冗长的 flat 单调的,沉闷的 dull 乏味的,单调的 troublesome 令人烦恼的,讨厌的,麻烦的 tired 疲劳的,累的 bored 无聊的,无趣的,烦人的 exhausted 极其疲倦的 weary 疲劳的 bright 聪敏的,机灵的 apt 聪明的,反应敏捷的 intelligent 聪明的,有才智的 shrewd 机灵的,敏锐的,精明的(表示生意上的精明) ingenious (人,头脑)灵巧的 alert 警觉的,留神的 cute 聪明伶俐的,精明的 acute/cute acute 指的是视力,感觉的敏锐 dull 愚钝的,笨的 awkward 笨拙的,不灵巧的 absurd 荒谬的 ridiculous 可笑的,荒谬的 idiotic 白痴般的 blunt 率直的,直言不讳的 clumsy 笨拙的,粗陋的 happy 快乐的,幸福的 cheerful 欢乐的,高兴的 content 满意的,满足的 merry 欢乐的,愉快的,快乐的 pleasure 高兴,愉快,满足 enjoyment 享乐,快乐,乐趣 cheer 喝彩 applause 鼓掌,掌声 optimism 乐观,乐观主义 delight 快乐,高兴 kick 极大的乐趣 paradise 天堂,乐园 instant 立即的,即刻的 instantaneous 瞬间的,即刻的 immediate 立即的,即刻的 simultaneous 同时发生的,同时存在的,同步的punctual 严守时刻的,准时的,正点的 pick 挑选,选择 select 选择,挑选 single 选出,挑出 elect 选举,推举 vote 投票,选举 appoint 任命,委派 nominate 提名,任命 propose 提名,推荐 recommend 推荐,举荐 designate 指派,委任 delegate 委派(或选举)…为代表 install(l) 使就职,任命 ballot 使投票表决 dub 把…称为 choice 选择(权) option 选择 selection 选择,挑选 alternative 取舍,供选择的东西 favorite 特别喜爱的人(或物) inclination 爱好 preference 喜爱,偏爱,优先 observe 注意到,察觉到 perceive 认识到,意识到,理解 detect 察觉,发现 appreciate (充分)意识到,领会,体会 alert 使认识到,使意识到 awake 意识到,醒,觉醒 scent 察觉 ancient 古代的,古老的 primitive 原始的 preliminary 预备的,初步的 preliminary trial初审 primary 最初的,初级的 initial 开始的,最初的 original 起初的 former 在前的,以前的 previous 先,前 prior 在前的,优先的 beforehand 预先,事先 medieval 中世纪的,中古(时代)的preceding 在先的,在前的,前面的 senior 资格较老的,地位较高的 following 接着的,下述的 attendant 伴随的 subsequent 随后的,后来的 succeeding 以后的,随后的 consequent 作为结果(或后果)的,随之发生的 resultant 作为结果的,因而发生的therefore 因此,所以 consequently 所以,因此 then 那么,因而 thus 因此,从而 hence 因此,所以 accordingly 因此,所以,于是 thereby 因此,从而

浅谈标点符号的正确使用

一、故事引入 杜牧的《清明》一诗“清明时节雨纷纷,路上行人欲断魂。借问酒家何处有,牧童遥指杏花村。”大家都很熟悉,但如果把标点符号改动一下,就成了另一作品。有人巧妙短句将其改成了一首词:“清明时节雨,纷纷路上,行人欲断魂。借问酒家何处?有牧童遥指,杏花村。”还有人改成了一首优美隽永的散文:“清明时节,雨纷纷。路上,行人欲断魂。借问酒家:“何处有牧童?”遥指杏花村。 又如,常有人在一路边大小便,有人就在那立了块牌子:过路人等不得在此大小便。立牌人的本意是:“过路人等,不得在此大小便。”可没有点标点符号,于是被人认为是:“过路人,等不得,在此大小便。” 类似的故事不胜枚举,诸如一客栈“下雨天留客天留我不留”的对联,祝枝山写给一财主的对联“今年正好晦气全无财富进门”。可见,标点符号的作用举足轻重。语文课程标准对小学各阶段学生应该掌握的标点符号作了明确的规定和说明。因此,作为小学语文教师,不但要咬文嚼字,教会学生正确使用标点符号也不容忽视。下面,我就简单谈谈一些易错的标点符号的用法。 二、易错标点符号的用法例谈 (一)问号 1、非疑问句误用问号 如:他问你明天去不去公园。虽然“明天去不去公园”是一个疑问,但这个问句在整个句子中已经作了“问”的宾语,而整个句

子是陈述的语气,句尾应该用句号。又如:“我不晓得经理的心里到底在想什么。”句尾也应该用句号。 2、选择问句,中间的停顿误用问号 比如:宴会上我是穿旗袍,还是穿晚礼服?这是个选择问句,中间“旗袍”的后面应该用逗号,而不用问号。再有:他是为剥削人民的人去死的,还是为人民的利益而死的?这个句中的停顿也应该用逗号。 3、倒装句中误把问号前置 像这样一个句子:到底该怎么办啊,这件事?原来的语序是:这件事到底该怎么办啊? 倒装之后,主语放到了句末,像这种情况,一般问号还是要放在句末,表示全句的语气。 4、介于疑问和感叹语气之间的句子该如何使用标点符号 有的句子既有感叹语气,又有疑问的语气,这样的情况下,哪种语气强烈,就用哪个标点,如果确定两种语气的所占比重差不多,也可以同时使用问号和叹号。 (二)分号 1、句中未用逗号直接用分号 从标点符号的层次关系来看,应该是逗号之间的句子联系比较紧密,分号之间的句子则要差一个层次,这样看来,在一个句中,如果没有逗号径直用分号是错误的。比如:漓江的水真静啊,漓江的水真清啊,漓江的水真绿啊。这里句中的两处停顿就不能使用分号。再

螺纹通止规要求螺纹通规通

螺纹通止规要求螺纹通规通,止规止。 但是如果螺纹通规止,说明什么? 螺纹止规通,又说明什么? 我也来说两句查看全部回复 最新回复 ?wpc (2008-11-07 20:11:20) 在牙型正确的前提下螺纹通止规检测螺纹中径 ?lobont (2008-11-08 11:16:32) 对外螺纹而言,螺纹通规是做到中径上偏差,所以能通过就表示产品合格,通不过就表示螺纹做大了,要再修一刀; 螺纹止规做到中径下偏差,所以只能通过2~3牙,如果也通过,就表示外螺纹做小了,产品成为废品 ?qubin8512 (2008-11-18 15:36:05) 螺纹赛规与螺纹环规主要测量螺纹的中径。 ?datafield (2008-11-29 19:12:51) 检具不是万能的,只是方便而已。具体没什么的我有在哪本书上看过,是一本螺纹手册上的。 ?ZYC007 (2009-2-09 20:31:13) 在牙型正确的前提下螺纹通止规检测螺纹中径。 对外螺纹而言,但是如果螺纹通规止,说明螺纹中径大;螺纹止规通,又说明螺纹中径小。 ?WWCCJJ (2009-3-19 09:27:19) 检测的是螺纹的中径,螺纹检测规在检定时,也是检测其中径. ?tanjiren (2009-3-20 22:23:06) 螺纹通止规只能检测螺纹的作用中径,大径和底径等均无法准确测量出来. ?月夜(2009-4-01 21:47:13) 用来测量中径 ?丽萍(2009-4-02 10:11:41)

只能检测工件螺纹的中径 yg196733456 (2009-4-03 09:15:56)原来是测中径的知道了

boring 和bored的区别

不能片面说人做主语用ed,物做主语ing ing形式是修饰引起这种感觉的人或物;ed形式是描写人或物的感受。(当然物一般是动物) 翻译的话 ing形式的词译为“令人……的”;ed形式译为“……的” boring是令人感到厌烦的;bored是厌烦的。 a boring person 能够指一个了无情趣的人,让人觉得无趣的人 a bored person 则是说这个人自己感到很无趣 1.bore 1)vt.使厌烦;挖 e.g. I'm bored with this job. 这件工作厌烦了。 The oldier bore the sharp pain in the wound with great courage. 这士兵以巨大的勇气忍受着伤口的剧烈疼痛。 2)n.令人讨厌的人(或事) e.g. It's a bore having to go out again. 外出真是讨厌。 boredom n.厌倦,无趣 e.g. in infinite boredom 极其无趣 boring n. 钻(孔) adj. 令人厌烦的(事或物) e.g. The play was boring. 这部短剧很一点意思都没有。 bored adj. 无聊的, 无趣的, 烦人的 e.g. Jack is so bored. 杰克是个没有趣的人。 2.surprising 是针对事或物感到惊奇。 surprised 则是针对人。 3.pleasant adj. 愉快的, 快乐的, 舒适的, 合意的可爱的, 举止文雅的, 活泼的滑稽的, 有趣的 (天气)晴朗的, 美好的容易相处的, 友爱的 e.g. a pleasant voice 悦耳的声音 a pleasant companion 可爱的伴侣 a pleasant time 愉快地度过时光 pleasing adj. 舒适的, 使人愉快的; 满意的; 惹人喜欢的, 可爱的 e.g. a pleasing look 使人愉快的神情 a very well mannered and pleasing young man 彬彬有礼而令人喜爱的年轻人

编校一课丨连接号用法大全

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