Answer Happy

1. Solve the following. a.) An air compressor (an open system) receives 272 kg per min of air 99.29 kPa and a specific volume of 0.026 cu.m/kg. The air flows steady through the compressor and is discharged at 689.5 kPa and 0.0051 cu.m/kg. The initial internal energy of the air is 1594 J/kg; at discharge, the internal energy is 6241 J/kg. The cooling water circulated around the cylinder carries away 4383 J/kg of heat. The change in kinetic energy is 896 J/kg increase. Sketch an energy diagram. Compute the work. b.) A centrifugal pump operating under steady flow condition delivers 2,270 kg/min of water from an initial pressure of 82,740 Pa to a final pressure of 275,800 Pa. The diameter of the outlet and inlet pipe to the pump is 10.16 cm. What is the work? c.) A turbine operates under steady flow conditions, receiving steam at the following state: pressure 1200 kPa, temperature 188°C, enthalpy 2785 kJ/kg, speed 33.3 m/s and elevation 3 m. The steam leaves the turbine at the following state; pressure 20 kPa, enthalpy 2512 kJ/kg, speed 100 m/s and elevation 0 m. Heat is lost to the surroundings at the rate of 0.29 kJ/s. If the rate of steam flow through the turbine is 0.42 kg/s, what is the power output of the turbine in kW?