空气压缩制冷循环的p-v图和T-s图T3T与燃气机布雷顿循环的比较?p300
1 2 3 4 T s T3 T1 空气压缩制冷循环的p-v图和T-s图 1 3 2 4 p v T0 Tc 与燃气机布雷顿循环的比较?p300
空气压缩制冷循环计算1.循环制冷量(制冷剂从低温热源吸收的热量)q。=h-h=c,(T-T)理想气体!T2.制冷剂放给高温热源的热量o=h,-h,=C,(T-T)3ToT,3.制冷循环消耗的净功Wnet =Wc-We =(hz -h)-(h-h,)-=(h,-h)-(h-h)=91-92
( ) 1 4 T1 T4 q h h c c = − = p − 2 3 1 4 1 2 2 1 4 3 ( ) ( ) ( ) ( ) h h h h q q w w w h h h h net C E = − − − = − = − = − − − 二、 空气压缩制冷循环计算 1.循环制冷量(制冷剂从低温热源吸收的热量) 1 2 3 4 T s T0 T2 ( ) 0 2 3 T2 T3 q h h c = − = p − 2. 制冷剂放给高温热源的热量 3. 制冷循环消耗的净功 理想气体!
三、制冷系数(thecoefficientofperformanceCOP)Tt2AcAcP,C=ToW.qi-qcnetTTc7qc=h -h4i=h-hWnet=h-h-(h-h.)=(h-h)-(h-h)0sT-Th-hAc8↑ (T-T)-(T-T)(h-h)-(h-h)WnetT1定比热(invariablespecificK-1T, -T,元 -1heatcapacityT=T元KP2循环增压比元三K-1PiT =T元K
三、制冷系数(the coefficient of performance COP) 1 2 3 q = h − h 定比热(invariable specific heat capacity) 1 3 4 1 2 1 − − = = T T T T C C net 1 C q q w q q = = − C 1 4 q h h = − ( ) ( ) ( ) w h h h h h h h h net 2 1 3 4 2 3 1 4 = − − − = − − − C net q w = = ( ) ( ) 2 3 1 4 1 4 T T T T T T − − − − 2 1 1 1 1 1 T T T − = − = − ( ) ( ) 1 4 2 3 1 4 h h h h h h − = − − − 2 1 , p p = 循环增压比
讨论:TT.T8e1)相同温度的T,和T。T-TT-TT,-T2)元个,但会导致制冷量9P2T21元==DK-1P21元-1元T.Tc1Ic0s例A361255
讨论: 1) C 1 1 c 0 C 3 1 2 1 T T T T T T T T T = = = − − − 相同温度的T 0和TC 2) C q 例A361255 1 1 1 − = − ,但会导致制冷量
A361255导出以空气为工质的斯特林制冷机的工作系数解:TW=Wi-2 +W3-4netVL-R.T.In= R.T. In1WnetggV2V2-T21(T-T)=R.In811V2Tq=T,As34=T,R,InVV2T.Toqc83=CcT-TcWnet
导出以空气为工质的斯特林制冷机的工作系数。 解: w w w net 1 2 3 4 = + − − 1 C 34 C g 2 ln c v q T s T R v = = 1 1 g 0 g C 2 2 ln ln v v R T R T v v = −( ) 1 g 0 C 2 ln v R T T v = − C C c net 0 C q T w T T = = = − A361255