our compression refrigerator operates between the pressure limits of 462.4 kN/m² and 1785.9 kN/m². At entry to compressor the refrigerant is dry saturated and after compression it has a temperature of 59°C. The compressor has boreand stroke of 75 mm and runs at 8 rev/sec. With volumetric efficiency of 30% The temperature of the liq. refrigerant as it leaves the condenser is 32°C and specific heat capacity of the super heated vapour may be assumed constant. Determine (1) The coefficiency of performance of refrigerator. (1) The mass flow of the refrigerant in kg/hr.

our compression refrigerator operates between the pressure limits of 462.4 kN/m² and 1785.9 kN/m². At entry to compressor the refrigerant is dry saturated and after compression it has a temperature of 59°C. The compressor has boreand stroke of 75 mm and runs at 8 rev/sec. With volumetric efficiency of 30% The temperature of the liq. refrigerant as it leaves the condenser is 32°C and specific heat capacity of the super heated vapour may be assumed constant. Determine (1) The coefficiency of performance of refrigerator. (1) The mass flow of the refrigerant in kg/hr.

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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9. A 9.5 tonnes capacity of ammonia refrigerator operates between evaporator and condenser temperature of -13°C and 28°C is needed in a food storage locker. The refrigerant is sub-cooled by 4°C before entering the expansion valve. The vapour is 0.90 dry as it leaves the evaporator coil. The compression in the compressor is adiabatic type. Using p-h chart find (i) Condition of vapour at outlet of the compressor (ii) Condition of vapour at entrance to evaporator (iii) С.О.Р. (iv) Power required in kW Neglect valve throttling and clearance effect.
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A 140 mm x 140 mm single effect , twin -cylinder , single acting Freon 12 compressorwith a refrigeration capacity of 40 Kw operates between a discharge pressure of 1300 KPa and asuction pressure of 350 KPa . The speed of the compressor is 600 rpm . If the discharge pressureshall be raised to 1400 KPa , at what speed (rpm) should the compressor be run to produce thesame refrigeration capacity and assuming the volumetric efficiency to remain the same ?A) 613 C) 630B) 621 D) 650
A refrigerant 12 refrigeration system requires a load of 54 kW at an evaporator pressure of 270 kPa and a condenser pressure of 1009 kPa. The refrigerant is subcooled 10 degrees before entering the expansion valve and vapor is superheated 14 degrees before entering the compressor A twin-cylinder compressor with stroke equal to 1.25 times the bore is to be used at a speed of 27 r/s The volumetric efficiency is 84 per cent. Determine (a) the quantity of cooling water in the condenser for an 11-degree increase in temperature, (b) the bore and stroke, and (c) the compressor power. Ans (a) 1.40 kg/s, (b) 8.58 x 10.73 cm, (e) 10.5 kW
saturated liquid from condenser Pcond = 900 kPa mcond =0.05 kg/s mcomp refrigerant to compressor ank- 500 kPa 3 rim mup Başka yönergeler almak için tıklayın Figure illustrates a vapor separator that is part of a refrigeration system. Saturated liquid R134a leaves the condenser at State 1 with a mass flow rate of 0.05 kg/s and pressure of 900 kPa. This refrigerant enters the vapor separator (a large, insulated tank) through a valve. The pressure in the tank is 500 kPa. There is no pressure drop due to flow through the tank (i.e., the pressure at States 2, 3, and 5 are all the same). The flow at State 2 is two-phase. The liquid portion of this flow falls to the bottom of the tank due to gravity while the vapor portion remains at the top. The saturated liquid is drawn from the bottom of the tank (at State 3). The saturated vapor is drawn off of the top of the tank at State 5 and fed to a compressor. Assume that the vapor separator is adiabatic, rigid, and operating at steady state. a) The…
In a refrigerant 12 system which serves a 250 kw evaporator at -30°C. The system uses two stage compression with intercooling and removal of flash gas. The condenser temp is 40°C. h2 = 357 kJ/kg, h4 = 365 kJ/kg Compute the ff:- mass flow rate at low stage compressor (m1), answer must be in kg/s- mass flow rate at high stage compressor (m3), answer must be in kg/s- low stage compressor work, answer must be in kw