Refrigerant 134a enters the evaporator of a refrigeration system operating at steady state at -8°c and quality of 15% at a velocity of 7 m/s. at the exit, the refrigerant is a saturated vapor at a temperature of -8°c. the evaporator flow channel has constant diameter. if the mass flow rate of the entering refrigerant is 0.4 kg/s, determine: (a) the diameter of the evaporator flow channel, in cm. (b) the velocity at the exit, in m/s.

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