5.0 A 140 x 140-mm, twin-cylinder, single acting refrigerant- 12 compressor running at 600 rpm carries a refrigeration capacity of 40 kW while operating at 350 kPa suction and 1300 kPa discharge pressures. Assuming the same load to be carried with the same volumetric efficiency and if the discharge pressure shall be raised to 1400 kPa, a) what is the percent increase in mass of R-12 (b)What will be the new volumetric displacement of the compressor in m/sec ?;(c)At what speed should the compressor be run?

5.0 A 140 x 140-mm, twin-cylinder, single acting refrigerant- 12 compressor running at 600 rpm carries a refrigeration capacity of 40 kW while operating at 350 kPa suction and 1300 kPa discharge pressures. Assuming the same load to be carried with the same volumetric efficiency and if the discharge pressure shall be raised to 1400 kPa, a) what is the percent increase in mass of R-12 (b)What will be the new volumetric displacement of the compressor in m/sec ?;(c)At what speed should the compressor be run?

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

See similar textbooks

Similar questions

a 140x140-mm, twin-cylinder, single acting refrigerant-12 compressor running at 600 rpm carries a refrigeration capacity of 40kW while operating at 350 kPa suction and 1300 kPa discharge pressures, assuming the same load to be carried with the same volumetric efficiency and if the discharge pressure shall be raised to 1400 kPa, a) what is the percent increase in mass of R-12 b.) what will be the new volumetric displacement of the compressor in m3/sec c.) at what speed should the compressor be run?
(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.
6.1) A boiler produces 25 kg/s of steam at 3 MPa and 600 °C, cools the condenser with seawater so that the outlet is at 45 °C, then a reheating at 500 kPa up to 400°C is carried out, then a low-pressure expansion is carried out in the turbine. Determine: A) The net power output B) The total heat transfer in the boiler Boiler Pump www اپنا Be Turbine Condenser آلفا Ans= A) 34820 kW B) 91733 kW
2) A R22 twin-cylinder 92x110 mm compressor operating at 1680 rpm, a condensing pressure of 1500 kPa and an evaporating pressure of 380 kPa carries a refrigerating capacity of 23.5 TOR. The motor driving the compressor has an efficiency of 92% and draws 30 kW. There is 5 degree subcooling on the liquid before entering TEV. Calculate a) the actual volumetric efficiency b) the compression efficiency.
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.
iii) the exit area of the nozzle. Take Cp = 1.005 kJ/kg-K and R=287 J/kg-K Q.B3. A heat engine operates between two reservoirs at 400°C and 30°C. Half the power produced by the heat engine is used to drive a Carnot heat pump that removes heat from the cold surroundings at 2°C and transfers it to a house maintained at 27°C. The heat engine is absorbing heat at a rate of 5 kJ/s. i) Draw the complete schematic of the device ii) Determine the thermal efficiency of the heat engine iii) Determine the coefficient of performance of the heat pump iv) Determine the rate of heat loss from the house. v) Determine the minimum rate of heat extraction by the heat pump, and vi) the total rate of heat rejection.
8. A turbine passes 67.5 kg/h of steam at 200 km/h at 8 MPa and leaves at 0.5 MPa as wet steam with a speed of 90 km/h and a specific volume of 0.189 m3/kg. d. What must be the steam input conditions (T,H) to turn on a device that consumes 30 kW? and. What is the mass and volumetric flow rate of the water at the outlet? F. What is the input and output area?
3.5 An ammonia refrigeration system operates between saturated suction temperature of -20°C, and saturated discharge temperature of +40°C. Com- pare the COP of the cycle using wet compression with that of the cycle using dry compression. Assume that the vapour leaving the compressor is saturated in the case of wet compression, and the vapour entering the compressor is saturated in the case of dry compression. The refrigerant leaves the condenser as saturated liquid.
The air entering the turbine with 1200 K and 1200 kPa expands to 100 kPa pressure in two stages. When the air is reintroduced to 1200 K at a constant reheat pressure of 350 kPa and both expansion stages are ideally realized: a) Total expansion work (kJ/kg) b) Intermediate heating amount (kJ/kg) c) Calculate the rate of increase in work according to the stepless (without reheating) expansion. Features for air: k=1,4, R=0,287 Jkg K,F1,005 klkg K k = 1.4 R = 0.287 kJ/kgK Cp = 1.005 kJ/kgK %3D
2) A R22 twin-cylinder 92x110 mm compressor operating at 1680 rpm uses R22 as refrigerant with a condensing pressure of 1355 kPa and an evaporating pressure of 380 kPa carries a refrigerating capacity of 23.5 TOR. The motor driving the compressor has an efficiency of 92% and draws 30 kW. If the compressor clearance is 10% calculate a) the clearance volumetric efficiency b) the actual volumetric efficiency c) the compression efficiency.
Q4: Why the stroke length of the racing cars' engines is always smaller than its bore diameter?
3. A water-tube boiler having a heating surface of 325.23 m² evaporates 6349.21 kg of water in an hour from a feed temperature of 66 °C. Boiler pressure is at 1.04 MPaa and the steam quality at the boiler outlet is 99 %. What percent of its rated Bo. Hp was the boiler developing?