27. Turbine Steam flows steadily through an adiabatic turbine. The inlet conditions of the steam are 10 Mpa, 450 o C and 80 m/s. The exit conditions are 10 kPa, 92 % quality and 50 m/s. The mass flow rate of steam is 12 kg/s. Determine: a. power output b. the turbine inlet area

28. Compressor Helium is compressed from 120 kPa and 310 K to 700 kPa and 430 K. Heat loss of 20 kJ/kg occurs during the process. Neglecting kinetic energy changes, determine the power input required for a flow rate of 90 kg/min.

29. Nozzle Air enters a nozzle at 300 kPa, 200 o C and 30 m/s and leaves at 100 kPa and 180 m/s. The inlet area is 80 cm 2. Determine: a. the mass flow rate through the nozzle b. the exit temperature of the air c. the exit area of the nozzle

30. Throttle/Expansion Valve R134a enters an expansion valve as saturated liquid at 1.2 Mpa and it is expanded adiabatically to 120 kPa. What is the temperature change across the valve? How would the result change if an ideal gas were used as the working fluid?

31. Mixing Chamber A person takes a shower using hot water (from “tanked” hot water heater) at 65 o C and cold water at 15 o C. The total flow rate is 2.5 gallons per minute and the shower temperature is 45 o C. Determine the volumetric flow rates of hot and cold water, in gallons per minute.

32. The Shower Continued As the shower continues, the temperature of the water coming out of the showerhead steadily decreases, even though the hot and cold water flow rates remain constant. Explain what is happening and include a diagram.

33. Mixing Chamber A person takes a shower using saturated water vapor at 100 o C and cold water at 15 o C. The total flow rate is 2.5 gallons per minute and the shower temperature is 45 o C. Determine the volumetric flow rates of hot and cold water, in gallons per minute.