Question

A hot-water stream at 80°C enters a mixing chamber with a mass flow rate of 0.46 kg/s where it is mixed with a stream of cold water at20°C. If it

is desired that the mixture leave the chamber at 42°C, determine the mass flow rate of the cold-water stream. Assume all the streams are at a pressure of 250 kPa. The enthalpies are 335.02 kJ/kg, 83.915 kJ/kg, and 175.90 kJ/kg. The saturation temperature ata pressure of 250 kPa is 127.41°C.

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