Refrigeration cycle vapor-compression

Vapor-Compression Cycles The most widely used refrigeration principle is vapor compression. Isothermal processes are realized through isobaric evaporation and condensation in the tubes. Standard vapor compression refrigeration cycle (counterclockwise Ranldne cycle) is marked in Fig. ll-72<7) by I, 2, 3, 4. 

Does the ideal vapor compression refrigeration cycle involve any internal irreversibility ... 

An actual vapor compression refrigeration cycle operates at steady state with R-134a as the working fluid. Saturated vapor enters the compressor at 263 K. Superheated vapor enters the condenser at 311K. Saturated liquid leaves the condenser at 301 K. The mass flow rate of refrigerant is 0.1 kg/sec. Determine... 

R-134a enters the compressor of a steady-flow vapor compression refrigeration cycle as superheated vapor at 0.14 MPa and — 10°C at a rate of 0.04 kg/sec, and it leaves at 0.7 MPa and 50°C. The refrigerant is cooled in the condenser to 24°C and saturated liquid. Determine (a) the compressor power required, (b) the rate of heat absorbed from the refrigerated space, (c) the compressor efficiency, and (d) the COP. 

Figure 92 Vapor-compression refrigeration cycle on a PH diagram.

Consider the vapor-compression refrigeration cycle of Fig. 9.1ft with Freon-12 as refrigerant the evaporation temperature is 10(°F), show the effect of condensation temperature on the coeffi of performance by making calculations for condensation temperatures of 60, 80, and 100(°F). 

In comparing the performance of a real cycle with that of a Carnot cycle, one has in principle a choice of temperatures to use for the Carnot calculation. Consider a vapor-compression refrigeration cycle in which tlie average fluid temperatures m the condenser and evaporator are Th aiid Tc, respectively. Corresponding to Th and Tc, tlie heat transfer occurs with respect to surroundings at temperature T , and Which provides the more conservative estimate of j(Camot) a calculation based on Th and Tc, or one based on Ts and... 

This is like Illustration 3.7-2 except that the Rankine rather than vapor compression refrigeration cycle is used. Only properties of point 2, and path from 1 — 2 changes. 

Figure 5.2-4 (a) The vapor-compression refrigeration cycle. (/ ) The vapor-compressron refrigeration cycle on T-S and P-H diagrams. 

The coefficient of performance (C.O.P.) for the vapor-compression refrigeration cycle is - ... 

DRY COMPRESSION - The compression of vapor, in a vapor-liquid vapor-compression refrigeration cycle. 

The net effect of this vapor compression refrigeration cycle, and its incorporation into a vapor degreaser, is to transfer heat from the hot solvent vapor above the boiling and rinsing sumps to ambient air adjacent to the cleaning machine. 

Refrigeration systems are important in industrial and home use when temperatures less than the ambient environment are required. Of the several types of refrigeration systems, the most widely used is the vapor-compression refrigeration cycle. It is essentially a Rankine cycle operated in reverse, where heat is absorbed from a cold reservoir and rejected to a hot reservoir. Due to the constraints of the second law, this process can be accomplished only with a concomitant consumption of power. 

Figure 3.9 The ideal vapor-compression refrigeration cycle. The four unit processes are sketched on the left, while the path on a Ts diagram is shown on the right.

Estimation of the COPof a Vapor-Compression Refrigeration Cycle... 

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