Pump - Constant Isentropic Efficiency Model

Model description

The constant isentropic efficiency model is a simple model based on the assumption that the isentropic efficiency stays constant.

\[\epsilon_{is} = \frac{h_{su} - h_{ex, is}}{h_{su} - h_{ex}}\]

where \(\epsilon_{is}\) is the isentropic efficiency, \(h_{su}\) is the supply specific enthalpy, \(h_{ex, is}\) is the isentropic exhaust specific enthalpy and \(h_{ex}\) is the exhaust specific enthalpy.

Based on the isentropic efficiency definition, the exhaust specific enthalpy can be calculated and thus also the exhaust temperature.

Class description

class component.pump.pump_csteff.PumpCstEff[source]

Component: Pump

Model: Constant efficiency

Descritpion:

This model determines the exhaust specific enthalpy and the exhaust temperature of a pump. This model can be used for on-design models of systems.

Assumptions:

  • Steady-state operation.

  • Efficiency stays constant for all the conditions.

Connectors:

su (MassConnector): Mass connector for the suction side.

ex (MassConnector): Mass connector for the exhaust side.

W (WorkConnector): Work connector for the pump power consumption.

Parameters:

eta_is: Isentropic efficiency. [-]

Inputs:

P_su: Suction side pressure. [Pa]

T_su: Suction side temperature. [K]

m_dot : Suction side flowrate [kg/s]

P_ex: Exhaust side pressure. [Pa]

fluid: Suction side fluid. [-]

Ouputs:

h_ex: Exhaust side specific enthalpy. [J/kg]

T_ex: Exhaust side temperature. [K]

Example of use


from labothappy.component.pump.pump_csteff import PumpCstEff
import numpy as np

# Example usage
PP = PumpCstEff()

# Set initial conditions
PP.su.set_properties(P=319296.56, T=331.03, fluid='R1233ZDE')
PP.su.set_m_dot(1.0)  
PP.ex.set_properties(P=606240.14, fluid='R1233ZDE')
PP.set_parameters(eta_is=0.9)
PP.solve()
PP.print_results()

References

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