An industrial plant has available a 4 cylinder, 3 in bove by an, stroke, 800 rpm, single-acting compressor for use with R-134a- Proposed operating conditions for the compressor are 100°F condensing temperature and 40°F evaporating temperature. It is estimated that the refrigerant will enter the expansion value as a saturated liquid that the vapor will leave the evaporator at temperature of 45°F and that vaper will enter the compress or at a temperature 55°p. Assumes a compressor volumetric efficiency of 70% and frictionless flow. Calculate the refing- erating capacity in tons for a system equipped with this compressor. Plot

An industrial plant has available a 4 cylinder, 3 in bove by an, stroke, 800 rpm, single-acting compressor for use with R-134a- Proposed operating conditions for the compressor are 100°F condensing temperature and 40°F evaporating temperature. It is estimated that the refrigerant will enter the expansion value as a saturated liquid that the vapor will leave the evaporator at temperature of 45°F and that vaper will enter the compress or at a temperature 55°p. Assumes a compressor volumetric efficiency of 70% and frictionless flow. Calculate the refing- erating capacity in tons for a system equipped with this compressor. Plot

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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(a) What would be the necessary bore and stroke of a single acting four- cylinder, 350 rpm ammonia compressor working on simple saturation cycle between 35°C condenser and -15°C evaporator temperatures and developing 15 tons refrigeration. Given for the compressor: Ratio of stroke to bore = 1 Volumetric efficiency = 0.7 (b) If the index of compression is 1.15, find the error introduced in calculat- ing the work of compression by assuming the process to be isentropic. Also, find the heat rejected to the compressor-jacket cooling water.
Q.2: A refrigeration system using refrigerant 22 is to have a refrigerating capacity of 80 kW. The cycle is a standard vapor-compression cycle in which the evaporating temperature 42°C. -8°C and the condensing temperature (a) Determine the volume flow of refrigerant measured in cubic is meters inlet at the to the compressor. second per (b) Calculate the power required by the compressor. (c) At the entrance to the evaporator what is the fraction of vapor in the mixture.
derive the general formula for the intercooling related to the number of stage of compressor
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