Compressor and the isentropic efficiency of the compressor

Assignment Help Mechanical Engineering
Reference no: EM13717737

A refrigeration unit operating on R-134a is used to maintain a freezer at -15°C. The refrigeration unit operates at a suction pressure of 140kPa and a discharge pressure of 900kPa. The condenser of the refrigeration unit is cooled by a water cooled heat exchanger. Cooling water flows through the condenser heat exchanger at a rate of 50kg/min, entering at a temperature of 20°C and leaving at a temperature of 29°C. It is known that the refrigeration unit can be modelled as an ideal vapour compression cycle for the heat rejection, throttling and heat absorption stages; however the compressor is known to be non-isentropic. The discharge temperature from the compressor is 60°C.

1) Determine the mass flow rate of the refrigerant, assuming a constant specific heat for the cooling water of C water=4.184 kJ/(kg.K).

2) What is the required power input to the compressor and the isentropic efficiency of the compressor?

Reference no: EM13717737

Determine the systems thermal efficiency

Air enters a three-stage gas turbine at 100 kPa and 17 degree Celsius. This system uses a regenerator as well as reheating and interfolding. The pressure ratio across each com

An adiabatic compressor compresses nitrogen

An adiabatic compressor compresses nitrogen (k=1.4, R=0.297) from P1=200 kPa and T1=300K to P2=1500kPa. The isentropic efficiency of the compressor is 80%, mass flow rate is 2

Determine the travel speed

Assume that the melting factor = 0.25. A continuous fillet weld is to be made with a cross-sectional area = 15.0 mm2 . Determine the travel speed at which the welding operat

Coefficient between hot process fluid and cold water

Determine the overall heat transfer coefficient between the hot process fluid and the cold water bath. Assume the properties of the hot process fluid are those of water.

Determine the mass flow rate through the nozzle

Air enters a nozzle steadily at 2.21 kg/m^3 and 30 m/s and leaves at 0.762 kg/m^3 and 180 m/s. If the inlet area of the nozzle is 80 cm^2 determine a) The mass flow rate throu

Is a probate estate subject to income tax

How does the gross estate differ from a probate estate What determines whether an item passes to heirs outside the probate process? Are there items subject to estate tax tha

Differences between these values on an atomistic basis

Where k is the coefficient of thermal conductivity. Look up reasonable values for these parameters, and compare the TSR of quartz, soda-lime and borosilicate (Pyrex) glass.

Thin walled tube with closed ends has an inside radius

A thin walled tube with closed ends has an inside radius of 80mm and a wall thickness of 6 mm. It is subjected to an internal pressure of 20 MPa, a torque of 60 kN*m, and an a


Write a Review

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd