In large steam power plants, the feedwater is frequently heated in closed feedwater heaters (basically heat...

In large steam power plants, the feedwater is frequently heated in closed feedwater heaters (basically heat exchangers) by steam extracted from the turbine at some stage. Steam enters the feedwater heater at 1.5 MPa and 250℃ and leaves as saturated liquid at the same pressure. Feed water enters the heater at 2.5 MPa and 60℃ and leaves at 10℃ below the exit temperature of the steam. Neglecting any heat losses from the outer surfaces of the heater, determine (a) the ratio of the mass flow rates of the extracted steam and the feedwater heater and (b) the total entropy change for this process per unit mass of the feedwater.

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samet mamat answered 1 year ago

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