Liquid water enters a heat exchanger operating at steady state at t1 = 60°f, p1 = 1 atm and exits at t2 = 160°f with a negligible change in pressure. in a separate stream, steam enters at t3 = 20 lbf/in^2, x^3 = 92% and exits at t = 140°f, p4 = 18 ibf/in^2. stray heat transfer and the effects of motion and gravity are negligible. let to = 60°f, po = 1 atm. determine (a) the ratio of the mass flow rates of the two streams and (b) the rate of exergy destruction, in btu per lb. of steam entering the heat exchanger.

Agas contained within a piston-cylinder assembly e end nation about same energy states, 1 and 2, where pi 10 bar, v undergoes two processes, a and b, between the sam 0.1 m3, ui-400 kj and p2 1 bar, v2 1.0 m2, u2 200 kj: process a: process from 1 to 2 during which the pressure- volume relation is pv constant process b: constant-volume process from state 1 to a pressure of 2 bar, followed by a linear pressure-volume process to +20 0 state 2 kinetic and potential energy effects can be ignored. for each of the processes a and b, (a) sketch the process on p-v coordinates, (b) evaluate the work, in kj, and (c) evaluate process the heat transfer, in kj