Engineering, 06.05.2020 00:45 preety5445

A vapor compression refrigeration cycle has an evaporator pressure of 201.7kPa and employs R-134a as the working fluid. The refrigerant circulates in the cycle at the rate of 3 kg/s. The cycle is comprised of a compressor, a condenser, an evaporator, and an expansion valve. The refrigerant leaving the evaporator and entering the compressor is saturated vapor. Compression in the compressor is not isentropic with the refrigerant leaving the compressor and entering the condenser at 60o C and 1000kPa. Refrigerant leaving the condenser and entering the expansion valve is saturated liquid. Find the following: (a) power consumption in the compressor (kW), (b) rate of heat addition to the evaporator (kW), (c) condenser heat rejection rate (kW), (d) cycle coefficient of performance, (e) compressor isentropic efficiency, (f) entropy generation rate in the expansion valve (kW/K), and (g) the irreversibility rate in the expansion valve in kW if the ambient temperature is 5o C. (7 points)

Answers: 1

Show answers

Another question on Engineering

Engineering, 04.07.2019 18:10

Which from the following instrument is commonly used to detect the high pitch butzing sound in bearings? [clo4] a)-digital ultrasonic meter b)-infrared camera c)-spectroscopic d)-vibrometer

Answers: 2

Answer

Engineering, 04.07.2019 18:10

Aturning operation is performed with following conditions: rake angle of 12°, a feed of 0.35 mm/rev, and a depth of cut of 1.1 mm. the work piece is aluminum alloy 6061 with t6 heat treatment (a16061-t6). the resultant chip thickness was measured to be 1.0 mm. estimate the cutting force, fc. use shear stress of 207 mpa and coefficient of friction on the tool face of 0.6.

Answers: 1

Answer

Engineering, 04.07.2019 18:20

Have a greater impact on maintenance productivity than any other support group. (clo5) a)-the top management b)-inventory and purchasing c)-sub-contracting d)-cmms

Answers: 2

Answer

Engineering, 04.07.2019 18:20

A3-mm-thick panel of aluminum alloy (k 177 w/m-k, c 875 j/kg-k and ? = 2770 kg/m) is finished on both sides with an epoxy coating that must be cured at or above t,-150°c for at least 5 min. the production line for the curing operation involves two steps: (1) heating in a large oven with air at ts,0-175°c and a convection coefficient of h, 40 w/m2. k, and (2) cooling in a large chamber with air at 25°c and a con- vection coefficient of he 10 w/m2.k. the heating portion of the process is conducted over a time interval te which exceeds the ime required to reach 150°c by 5 min (h = r + 300 s). the coating has an emissivity of ? = 0.8, and the temperatures of the oven and chamber walls are 175 and 25°c, respectively. if the panel is placed in the oven at an initial temperature of 25°c and removed from the chamber at a safe-to-touch tempera ture of 37°c, what is the total elapsed time for the two-step curing operation?

Answers: 3

Answer

You know the right answer?

A vapor compression refrigeration cycle has an evaporator pressure of 201.7kPa and employs R-134a as...

Questions