Analysis of parallel flow heat transfer Parallel flow heat exchanger At any location along the heat exchanger hot. in hotout dq=UaA△T coldout Define:△T =(Th-T)so:d△T=dh-d Where:d=m,cn,=C,T→d p, c d qh So p, d△T dq=UdA△T T Ud小 △T Integrating from the inlet to the outlet △T2\=U Eq.11.13 △T Heat Transfer Su Yongkang School of Mechanical EngineeringHeat Transfer Su Yongkang School of Mechanical Engineering # 12 Analysis of parallel flow heat transfer Parallel flow heat exchanger • At any location along the heat exchanger Where: • So: • Integrating from the inlet to the outlet Thot,in Tcold ,in Thot,out Tcold ,out dq dq =UdAT h h p h h h h c c c p c c c c c dq m c dT C dT C dq dq m c dT C dT dT = − = − = =  = , ,   ( ) h c d T dTh dTc Define : T = T −T so:  = − T d T C C UdA C C -d T dq UdA T h c h c   =         − + +  =  = 1 1 1 1 Eq. 11.13         = − +           Ch Cc UA T T 1 1 ln 1 2