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A power plant uses steam to drive a turbine in order to produce electricity for the national grid. As the steam expands through the turbine its pressure decreases from 15 bar to 1.5 bar. The steam enters the turbine with a temperature of {T_in} °C and emerges at the outlet as a saturated vapour. The turbine operates at steady state and outputs {W_dot} MW of power. You can assume that the heat losses and potential effects are negligible.

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Inlet temperature

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Inlet specific enthalpy

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Mass flow rate with negligable kinetic effects

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Mass flow rate with kinetic effects

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Inlet velocity

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Outlet specific enthalpy

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What is the enthalpy of the steam at the turbine’s inlet and outlet in kJ/kg?

\n

$h_{inlet}$ (kJ/kg) = [[0]]  

\n

$h_{outlet}$ (kJ/kg) = [[1]]  

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Calculate the mass flow rate of steam in kg/s if kinetic effects are negligible. 

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Calculate the mass flow rate of steam in kg/s if the steam’s outlet velocity is negligable compared to the {v_in} m/s inlet velocity. 

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