Find General Efficiency of Reciprocating Pumps

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The general efficiency of reciprocating pumps can be calculated using the formula η = P_out / P_in. Isentropic pump efficiency is specifically defined as η_p = (-W_dot_cv / ṁ)_s / (-W_dot_cv / ṁ), where (-W_dot_cv / ṁ)_s represents the change in enthalpy under isentropic conditions. The enthalpy changes are given by h_2s - h_1 for isentropic and h_2 - h_1 for actual conditions. Understanding these equations is crucial for evaluating pump performance. Accurate efficiency calculations are essential for optimizing reciprocating pump operations.
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Does anybody know where I can find the general efficiency of reciprocating pump?
 
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The general efficiency is:

\eta=\frac{P_{out}}{P_{in}}
 
More specifically, isentropic pump efficiency is defined as:

\eta_{p}=\frac{\left(-Wdot_{cv}/mdot\right)_{s}}{\left(-Wdot_{cv}/mdot\right)}

Where:

\left(\frac{-Wdot_{cv}}{mdot}\right)_{s}=h_{2s}-h_{1}
and
\left(\frac{-Wdot_{cv}}{mdot}\right)=h_{2}-h_{1}
 
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