【正文】 ll be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is diving into the shallow end. Skydiver preps for the big jumpWhen he jumps, he is expected to reach the speed of sound 690 mph (1,110 kph) in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him pletely.If he goes too fast or spins out of control, he has a stabilization parachute that can be deployed to slow him down. His team hopes it39。 Have declared the end of the encounter that haven39。那些曾經(jīng)所謂的非做不可，只是青蔥年華里自己給自己注射的一支強(qiáng)心劑，或者說(shuō)，是自以為是的精神寄托罷了。s time, your ideas are always special to clear. Want, want, line is clear, as if nothing could shake his. Also once seemed to be determined to do something, but more often is he backed out at last. Dislike his cowardice, finally found that there are a lot of love, there are a lot of miss, like shadow really have been doomed. Those who do, just green years oneself give oneself an arm injection, or is a selfrighteous spiritual.　　一個(gè)人的時(shí)候，自己的想法總是特別地清晰。t want to give vent to out your inner voice can be in the high school children of the feelings in a period, but was eventually infarction when graduation party in the throat, later again stood on the pitch he has sweat profusely, looked at his thrown a basketball hoops, suddenly found himself has already can39。The end of our life, and can meet many things really do?　　而窮盡我們的一生，又能遇到多少事情是真正地非做不可？During my childhood, think lucky money and new clothes are necessary for New Year, but as the advance of the age, will be more and more found that those things are optional。 May be back in the past, to oneself the paranoid weird belief disillusionment, these days, my mind has been very messy, in my mind constantly. Always feel oneself should go to do something, or write something. Twenty years of life trajectory deeply shallow, suddenly feel something, do it.　　一字開(kāi)頭的年齡已經(jīng)到了尾聲。s 21 win.Michel Platini, president of European football39。s about how he felt and I would like to speak to him first to find out what his experience was.Uefa hasEmployment tribunals.The (lack of) air up there Watch mCayman Islandsbased Webb, the head of Fifa39。a damagesbased agreement, you should make sure you39。Further help.If you are being represented by a solicitor at the tribunal, they may ask you to sign an agreement where you pay their fee out of your pensation if you win the case. This is known as at you don39。通過(guò)自學(xué)及老師的指導(dǎo)，不僅鞏固了所學(xué)的化工原理知識(shí),更極大地拓寬了我的知識(shí)面，讓我更加認(rèn)識(shí)到實(shí)際化工生產(chǎn)過(guò)程和理論的聯(lián)系和差別，這對(duì)將來(lái)的畢業(yè)設(shè)計(jì)及工作無(wú)疑將起到重要的作用. 致謝本次設(shè)計(jì)能完全結(jié)束，離不開(kāi)老師的辛勤指導(dǎo)和同學(xué)們的熱心幫助。不能太粗心，做錯(cuò)了也得認(rèn)真的改過(guò)來(lái)，不發(fā)脾氣爭(zhēng)取不再出錯(cuò)。找資料其實(shí)不難，關(guān)鍵是如何去辨別找到的資料是否有用，有時(shí)會(huì)找到兩套不同的數(shù)據(jù)，然后就得自己去辨別了。（4）設(shè)計(jì)幫助我認(rèn)識(shí)到團(tuán)隊(duì)的作用，一個(gè)優(yōu)秀的團(tuán)隊(duì)是事業(yè)成功的基石。由于我們的設(shè)計(jì)采用電子版，所以是我對(duì)WORD、EXCEL、CAD的操作更加熟悉。在設(shè)計(jì)中這樣是不行的，必須總體把握，統(tǒng)籌全局。首先談?wù)勎以诒敬卧O(shè)計(jì)中的收獲吧。每個(gè)孔直徑為。因?yàn)槿绻搀w厚度過(guò)薄，將導(dǎo)致剛度不足而極易引起過(guò)大的彈性變形，不能滿足運(yùn)輸、安裝的要求。輸送料液要求的軸功率小于輸送清水的軸功率，電動(dòng)機(jī)能滿足要求。2．此處計(jì)算的塔高是塔總高，即從塔的底座至塔頂封頭處的高度。為利于出塔氣體夾帶的液滴沉降，其高度是指塔頂?shù)谝粚铀P到塔頂封頭的直線距離，通常取為（～）HT。（2）計(jì)算殼程壓降 按式計(jì)算 , 對(duì)于氣體或蒸汽 流體流經(jīng)管束的阻力 管子為正三角形排列 F= （取值14） 取折流擋板間距z= 由于 D=500mm 殼程流通面積= 2殼程流體流速及其雷諾數(shù)分別為：+= m/s 14(29+1)= 流體流過(guò)折流板缺口的阻力 , z= , D= 總阻力 =（+）11= 由計(jì)算結(jié)果表明，殼程和管程的壓力降均能滿足設(shè)計(jì)條件。 （二）確定物性數(shù)據(jù)定性溫度：殼程流體定性溫度為T=℃管程流體的定性溫度為t=（20+28）/2=24℃ 查參考書(shū)[4] ℃下的有關(guān)物性數(shù)據(jù)：表16 物性數(shù)據(jù)表№密度（kg/m3）潛熱kJ/kg導(dǎo)熱系數(shù)正戊烷610225正己烷640210查得循環(huán)水在24℃ 下的物性數(shù)據(jù)：=(kg?℃) =(m?℃) =（三）估算傳熱面積，初選換熱器型號(hào)（1）傳熱量（忽略熱損失）℃時(shí)的汽化潛熱為r= Q==（2）冷卻水用量（忽略熱損失） = kg/s=49428kg/h（3）計(jì)算平均傳熱溫差 暫按單殼程、雙管程考慮由于=（）℃=℃=（）℃=℃ /=故可用算數(shù)平均溫度差=（+）/2=℃50℃由于殼程流體恒溫，故 ℃50℃根據(jù)換熱任務(wù)和流體性質(zhì)，初步選擇固定管板式換熱器。設(shè)計(jì)一臺(tái)列管式換熱器，完成該生產(chǎn)任務(wù)。取E=1，則 ………………………………………………………………………………(5) ②提餾段 取堰上液層高度作為液相負(fù)荷下限條件，依下列的計(jì)算式：，計(jì)算出的下限值，依此作出液相負(fù)荷下限線，該線為與氣相流量無(wú)關(guān)的豎直直線。依式知液體在降液管內(nèi)停留時(shí)間求出上限液體流量值（常數(shù)），在圖上，液相負(fù)荷上限線為與氣體流量無(wú)關(guān)的豎直線。因此，可將上式簡(jiǎn)化，得 …………………..(2)在操作范圍內(nèi)任取若干個(gè)值，依上式算出相應(yīng)的值列于下表13中表13 液泛線數(shù)據(jù)qV,L(m3/s)5E04qV,V(m3/s)②提餾段 同精餾段得到物系一定，塔板結(jié)構(gòu)尺寸一定，則，則、及等均為定值，而與又有如下關(guān)系，即：式中閥孔數(shù)N與孔徑亦為定值。圖6 泛點(diǎn)負(fù)荷圖 塔板負(fù)荷性能圖霧沫夾帶線按式作出①精餾段對(duì)于一定的物系及一定的塔板結(jié)構(gòu)，式中、及均為已知值，相應(yīng)于的泛點(diǎn)率上限值亦可確定，將各已知數(shù)代入上式，便得出的關(guān)系式，據(jù)此作出霧沫夾帶線?？捎孟率接?jì)算，即（1）與氣體通過(guò)塔板的壓降相當(dāng)?shù)囊褐?精餾段 提餾段 （2）液體通過(guò)降液管的壓頭損失，因不設(shè)進(jìn)口堰，故按式計(jì)算，即精餾段 提餾段 （3）板上液層高度①精餾段 取因此 則可見(jiàn)，符合防止淹塔的要求。①精餾段 因，則可按式計(jì)算，即=m②提餾段 因，則可按式計(jì)算，得=（2）板上充氣液層阻力 本設(shè)計(jì)分離正戊烷和正己烷的混合液，即液相為碳?xì)浠衔铮扇〕錃庀禂?shù)。依式計(jì)算鼓泡區(qū)面積，即浮閥排列方式采用等腰三角形叉排。取同一橫排的孔心距t=75mm=，則可按下式估算排間距，即考慮到塔的直徑較大，必須采用分塊式塔板，而各分塊的支承與銜接也要占去一部分鼓泡區(qū)面積，因此排間距不宜采用134mm，而應(yīng)小于此值，故取。提餾段 取，則故降液管底隙設(shè)計(jì)合理。圖4 和值與LW/D的關(guān)系由/D=，查圖得，Af/AT=，Wd/D=Af==（m2）Wd==（m2）液體在降液管中的停留時(shí)間一般不應(yīng)小于3~5s，以保證溢流液體中的泡沫有足夠的時(shí)間在降液管中得到分離。＜11＜110110～200200～300＜11＜110110～230230～350＜11＜110110～250250～400＜11＜110110～250250～450因此，由表9液相負(fù)荷與板上液流型式的關(guān)系表可知，整個(gè)精餾塔選用單溢流弓形降液管，采用凹形受液盤。計(jì)算得 =塔底液相平均黏度：由tw=℃ ，=，=。平均摩爾質(zhì)量 塔頂汽、液混合物平均摩爾質(zhì)量：由xD=y1=，查平衡曲線圖得x1=（見(jiàn)附圖2）。塔頂及塔釜溫度分別為：tD =℃ tw = ℃ 全塔平均溫度 tm=(+)/2=℃ 查參考書(shū)[4]得定性溫度下物料的粘度：實(shí)際板層數(shù)的求取精餾段實(shí)際板層數(shù) NP，精=3/=≈6提留段實(shí)際板層數(shù) NP，提=5/=≈10總實(shí)際板層數(shù) NP= NP，精+ NP，提=16 精餾塔的工藝條件及有關(guān)物性數(shù)據(jù)的計(jì)算操作壓力塔頂操作壓力 pD=p當(dāng)?shù)?p表=+4= kPa每層塔板壓降 Δp=進(jìn)料板壓力 pF=+6=精餾段平均壓力 pm1=(+)/2=塔底壓力 pw=（+16）=提鎦段平均壓力 pm2=（+）/2=操作溫度根據(jù)汽液相平衡數(shù)據(jù)畫(huà)出汽液相平衡圖，由不同部位的含量在圖（見(jiàn)附圖2）中查得塔頂、塔底及加料板處的溫度并計(jì)算精餾段、提鎦段的平均溫度。 tb