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Rankine Cycle: Screencasts

Describes the steps in a power cycle that converts high temperature heat into work using a turbine.

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Describes a Rankine power cycle with steam using a log pressure versus enthalpy diagram.

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

Important Equations:

Cycle thermal efficiency: \[\eta = \frac{|W_{net}|}{Q_H} = \frac{|W_{turbine}+W_{pump}|}{Q_H}\] where \(W_{net}\) is negative, \(W_{turbine}\) is negative, and \(W_{pump}\) is positive.

Energy balance for an adiabatic turbine: \[\Delta H = W_{turbine}\] where \(\Delta H\) is the enthalpy change across the turbine and \(W_{turbine}\) is the shaft work generated by the turbine.

Turbine efficiency: \[\eta = \frac{W_{irrev}}{W_{rev}}*100\] where \(W_{irrev}\) is the net work generated by an irreversible turbine and \(W_{rev}\) is the net work generated by a reversible turbine. Note that the same symbol \(\eta\) is often used for both a turbine efficiency and a cycle efficiency.

Entropy change for a reversible adiabatic turbine: \[\Delta S = 0\]