劉中良-北京工業(yè)大學(xué)-高等工程熱力學(xué)-第2講

1、by Professor Liu Zhongliang2by Professor Liu Zhongliang3by Professor Liu Zhongliang4by Professor Liu Zhongliang5by Professor Liu Zhongliang6mgzmcUEEUEpk221gzcueeuepk221by Professor Liu Zhongliang7by Professor Liu Zhongliang8 0dE2121DCdEdE12CDby Professor Liu Zhongliang9by Professor Liu Zhongliang10b

2、y Professor Liu Zhongliang11)(12WEEQby Professor Liu Zhongliang12by Professor Liu Zhongliang13Fi 廣義力，強度量廣義力，強度量xi 廣義位移，廣延量廣義位移，廣延量iidxFW by Professor Liu Zhongliang14by Professor Liu Zhongliang15WpdVWby Professor Liu Zhongliang16by Professor Liu Zhongliang17by Professor Liu Zhongliang18WQ0)(WQby Pro

3、fessor Liu Zhongliang19dEWQby Professor Liu Zhongliang20WdEQby Professor Liu Zhongliang21by Professor Liu Zhongliang22WpdVWWdEQWpdVdEQby Professor Liu Zhongliang23pVUHmgzmcHpVEH2021)(0pVddEdH)(0pVddHdEVdppdVdHdE0by Professor Liu Zhongliang24WpdVdEQWVdpdHQ0by Professor Liu Zhongliang25WVdpdHQWpdVdUQb

4、y Professor Liu Zhongliang26Q0 ,iihm 0 ,eehm sWby Professor Liu Zhongliang27l單位時間內(nèi)，CV儲存能的變化可以表示成， J/kg CV, into stream theofenthalpy totalkg/s CV, into flowrate mass 0iihm J/kg CV, ofout stream theofenthalpy totalkg/s CV, ofout flowrate mass 0eehm Wunit time,per CV fromoutput shaft work Wunit time,p

5、er CV intofer heat trans sWQddECVby Professor Liu Zhongliang28SiieeCVWmhmhddEQ00gzchh2021（1 1）多個物流怎么辦？）多個物流怎么辦？（2 2）如何導(dǎo)出穩(wěn)定流動）如何導(dǎo)出穩(wěn)定流動能能 量方程？量方程？by Professor Liu Zhongliang29by Professor Liu Zhongliang30by Professor Liu Zhongliang310em 0SW0Q0c0z00iiCVmhddE00ddmhddEiiCVSiieeCVWmhmhddEQ00by Professor L

6、iu Zhongliang3200iiCVdmhdE0001 ,iiCVCVmmiiEECVdmhdEconstTchhipii0iipiiCVCVmTcmhEE01 ,by Professor Liu Zhongliang33gases) ideal(for CVvCVTmcEiipCVvCVvmTcTmcTmc11 ,iipCVvvCVCVmTcTTmcTcmm)()(11 ,1 ,11 ,1 , ,mmmmmCViCVCVkccvpby Professor Liu Zhongliang34所以iiimkTTTmTm)(11從中解得，(a) 1111TkTTTmmmmmiCVi按理想氣體方

7、程，RTmpVRTmVpCV111by Professor Liu Zhongliang35TTppmmCV111TkTTTTTppi1111by Professor Liu Zhongliang36(b) 111111TTkppTTkTTii顯然，該式。依據(jù)充氣參數(shù)的不同，可能會出現(xiàn)三種情況：by Professor Liu Zhongliang371111111TTkppTTkTTii11111TTkppTTkiiby Professor Liu Zhongliang38(c) 11111TTkppTTkii11pp011TTkiby Professor Liu Zhongliang39(

8、d) 1TkTiby Professor Liu Zhongliang40(e) 1TkTi(f) 1TkTiby Professor Liu Zhongliang410.51.01.52.0kTi/T10.51.01.52.0T/ T10.50.250.1250pp /1by Professor Liu Zhongliang42(a) 1111TkTTTmmmmmiCVi(b) 111111TTkppTTkTTiiby Professor Liu Zhongliang43(g) 111111ppkTTmmmmmiCViby Professor Liu Zhongliang44ddmhddEd

9、QiiCV0SiieeCVWmhmhddEQ00iiCVdmhdEQ0by Professor Liu Zhongliang45ipiCVvCVTchdmTcdE01 iipCVvdmTcdmTcQ1iCVmiipmmCVvQdmTcdmTcQ0101iipCVvmTcmmTcQ)(11iCVmmm1by Professor Liu Zhongliang46)(1111mmTTkTcQCViv)(111ppRTVmmCV1111TTkkppVQi注意依據(jù)充氣條注意依據(jù)充氣條件的不同，件的不同，Q可可以大于零，也可以大于零，也可以小于零！以小于零！by Professor Liu Zhongli

10、ang47by Professor Liu Zhongliang48by Professor Liu Zhongliang49PMM2QWQEnvironmentby Professor Liu Zhongliang50United States Patent and Trademark Office ，USPTO Johnson, Howard R., US4151431 Permanent Magnet Motor, April 24, 1979 Baker, Daniel, US4074153 Magnetic propulsion device, February 14, 1978 H

11、artman; Emil T., US4215330 Permanent magnet propulsion system, December 20, 1977今年埃及科學(xué)家的發(fā)明熱巖CO2發(fā)電系統(tǒng)by Professor Liu Zhongliang51by Professor Liu Zhongliang52by Professor Liu Zhongliang53 0TQpvpvby Professor Liu Zhongliang54In the neighborhood (however close) of any equilibrium state of a system of a

12、ny number of thermodynamic coordinates, there exist states that cannot be reached (are inaccessible) by reversible adiabatic processes.by Professor Liu Zhongliang55by Professor Liu Zhongliang56by Professor Liu Zhongliang57熱力學(xué)熱力學(xué)吉布斯慣性原理穩(wěn)定平衡定律第一定律第二定律狀態(tài)公理第第0定律定律第三定律第三定律量子力學(xué)量子力學(xué)Schrodinger方程by Professo

13、r Liu Zhongliang58lA system having specified allowed states and an upper bound in volume can reach from any given state one and only one stable state and leave no net effect on its environmentby Professor Liu Zhongliang59by Professor Liu Zhongliang60A basic understandingNo further proving needed by

14、Professor Liu Zhongliang61可逆TQdS0孤立dSIsolated system是與外界既無能量交換，也無物質(zhì)交換的系統(tǒng)by Professor Liu Zhongliang62 任意系統(tǒng)它的環(huán)境孤立系統(tǒng)環(huán)境 于是，孤立環(huán)境系統(tǒng) dSdSdS0環(huán)境系統(tǒng)dSdSby Professor Liu Zhongliang630環(huán)境系統(tǒng)dSdSby Professor Liu Zhongliang640環(huán)境系統(tǒng)dSdSby Professor Liu Zhongliang65by Professor Liu Zhongliang66by Professor Liu Zhongli

15、ang67by Professor Liu Zhongliang68Clausius熱寂說熱寂說by Professor Liu Zhongliang69愛丁頓愛丁頓by Professor Liu Zhongliang70 by Professor Liu Zhongliang71對熱寂說的批判對熱寂說的批判by Professor Liu Zhongliang72恩格斯的偉大之處恩格斯的偉大之處by Professor Liu Zhongliang73熵方程（熵方程（Entropy Equation）按Clausius等式不等式,TQdS或者寫成等式：TQdSdSgproductionen

16、tropy 熵產(chǎn)，TQdSdSgflowentropy 熵流，TQdSfby Professor Liu Zhongliang74熵方程熵方程fgdSdSdSfgdSdSdSby Professor Liu Zhongliang75開口系統(tǒng)的熵方程開口系統(tǒng)的熵方程l不難理解，對于開口系統(tǒng)：l對于單位時間：ddSddSTQmsmsCVgiieeiiiiiieeCVgTQmsmsddSddSby Professor Liu Zhongliang76開口系統(tǒng)的熵方程開口系統(tǒng)的熵方程 K)J/(kg CV, into stream theofentropy kg/s CV, into flowrate

17、 mass iismK) W/(kgunit time,per CV of changeentropy K) W/(kgrate, productionentropy ddSddSCVg K)J/(kg CV, ofout stream theofentropy kg/s CV, ofout flowrate mass eesmK) W/(kg, CV into rate flowentropy iiTQby Professor Liu Zhongliang77熵產(chǎn)與熵增原理熵產(chǎn)與熵增原理l對于孤立系統(tǒng)孤立孤立)()(fgdSdSdS孤立)(gdS0可以簡單地表述為： ，即：0 0ddSdSg

18、gby Professor Liu Zhongliang78熵產(chǎn)與熵增原理熵產(chǎn)與熵增原理by Professor Liu Zhongliang80能質(zhì)能質(zhì)by Professor Liu Zhongliang81能質(zhì)能質(zhì)lQ1000kJ：來自1000K的熱源lQ1000kJ：來自500K的熱源l環(huán)境：300KTCT0QWTTQW0max1熱源熱源500K 400kJ1000K kJ700maxWby Professor Liu Zhongliang82能質(zhì)系數(shù)能質(zhì)系數(shù)TT01300840138019202460300000.20.40.60.81Tby Professor Liu Zhongl

19、iang83lExergy： 在，能量中能夠轉(zhuǎn)變?yōu)橛杏霉Φ哪遣糠帜芰縧Anergy： 不能轉(zhuǎn)變?yōu)橛杏霉Φ哪遣糠帜芰縝y Professor Liu Zhongliang84Exergyby Professor Liu Zhongliang85Calculation of Exergy 設(shè)系統(tǒng)從溫度為T的熱源吸熱q，環(huán)境溫度為T0，那么，按定義：anergy exergy 100,qTTexqbTTqwexqqrecqby Professor Liu Zhongliang86閉口系統(tǒng)工質(zhì)的閉口系統(tǒng)工質(zhì)的exergy 0環(huán)境系統(tǒng)dSdSby Professor Liu Zhongliang87閉口系統(tǒng)工質(zhì)的閉口系統(tǒng)工質(zhì)的exergy即 ds+ds0=0， 或 ds0=-ds按可逆過程熵的計算式：00TqdsdsTdsTq000dvpdudsTdexdexdvpdudsT0000)0(00)(dvpdudsTexby Professor Liu Zhong