In large steam power plants, the feedwater is frequently heatedin closed feedwater heaters (basically heat exchangers) by steamextracted from the turbine at some stage. Steam enters thefeedwater heater at 1.5 MPa and 250℃ and leaves as saturated liquidat the same pressure. Feed water enters the heater at 2.5 MPa and60℃ 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 extractedsteam and the feedwater heater and (b) the total entropy change forthis process per unit mass of the feedwater.
