Question

Substance Ammonia

This is an hypothetic Refrigeration cycle.

Draw the schematic for this case. (evaporator, compressors…)include the temperature and pressure line

Sketch the T-s and P-v diagram.        30 points.

Process

State 1        leaving the evaporator at -20 C and 175 kPa

State 2        leaving the Low pressure isentropic compressor at 5.5 bar and enter the high pressure irreversible compressor to state 3

State 3        135 C, 20 bar

State 4         isobaric condenses process (3-4) to saturated liquid

State 5 (4-5) expansion valve to 5.5 bar and enter to a flash chamber

The flash chamber receive the liquid-vapor mixture and separate the vapor and liquid. Its return the vapor to the High pressure compressor entry and the saturated liquid is tag as state 6

State 6 isobaric process to saturated liquid

State 7 (6-7) expansion valve to low pressure line enter the evaporator

Answer 1