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#### Refrigeration Cycle: Screencast

Explains each step in a refrigeration cycle and the energy balance for each step. The process is shown in a pressure-enthalpy diagram.

We suggest you list the important points in this screencast as a way to increase retention.

##### Important Equations:

Coefficient of performance: $COP = \frac{Q_C}{W_S}\,\,\,(COP > 1)$ where $$Q_C$$ is the heat added to the evaporator (low temperature part of the cycle) and $$W_S$$ is the work done by the compressor $$Q_C > 0, W_S>0)$$

Energy balance for adiabatic compressor: $\Delta H = W_S$ where $$\Delta H$$ is the enthalpy change across the compressor $$(\Delta H > 0)$$

Entropy ($$S$$) change for reversible adiabatic compressor: $\Delta S = 0$ Energy balance for evaporator: $\Delta H = Q_C$ where $$\Delta H$$ is the enthalpy change across the evaporator and $$Q_C$$ is the heat added at low temperature $$(Q_C > 0)$$

Energy balance for condenser: $\Delta H = Q_H$ where $$\Delta H$$ is the enthalpy change across the condenser and $$Q_H$$ is the heat removed at high temperature $$Q_H < 0$$

Energy balance for adiabatic throttle: $\Delta H = 0$ (no heat transfer and no work on throttle)