The Vapor Compression Cycle Reference Page

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Intro to The Vapor Compression Cycle

The vapor-compression cycle is the thermodynamic cycle used in most refrigerators, freezers, and air conditioners.
Work is supplied to a compressor to move heat from a low-temperature region to a higher-temperature environment.

Revenge of the Fridge: Vapor Compression Strikes Back

The video explains the vapor compression cycle, derives the coefficient of performance, and contrasts the cycle with the Rankine cycle.

Visuals

Modeling the Vapor Compression Cycle in DWSIM

This video is a how-to on modeling the vapor compression cycle in DWSIM

Examples and Definitions

Definitions

Refrigerator
A device that removes heat from a cold region and rejects that heat to the surrounding environment.
Heat Pump
A device that transfers heat from a colder external environment to a warmer internal space.
Vapor Compression Cycle
A thermodynamic refrigeration cycle consisting of four main steps:
  1. Isobaric heat absorption in the evaporator (low temperature)
  2. Isentropic compression in the compressor
  3. Isobaric heat rejection in the condenser (high temperature)
  4. Isenthalpic expansion through a throttling valve

Phase changes usually occur during both the evaporation and condensation stages.

Refrigerant
A fluid used in vapor-compression refrigeration cycles. Common refrigerants include R-134a, ammonia, and propane (R-290).
Coefficient of Performance, COP or \(\omega\)
The ratio of the desired heat transferred, (\(|Q_\mathrm{cold}|\) for a refrigerator, \(|Q_\mathrm{hot}|\) for a heat pump) to the work input.