Chapter 6, Problem 6.104P

Water vapor enters a turbine operating at steady state at 1000oF, 230 lbf/in2, with a volumetric flow rate of 25 ft3/s, and expands reversibly and adiabatically to 2 lbf/in2. Ignore kinetic and potential energy effects.    determine the mass flow rate in lb/s and  the power developed by the turbine in hp.

The entropy change between two specified states is the same whether the process is reversible or irreversible.

When two systems are in contact, the entropy transfer from the warmer system is equal to the entropy transfer into the cooler one at the point of contact. That is, no entropy can be created or destroyed at the boundary since the boundary has no thickness and occupies no volume.

Carbon dioxide gas is compressed at a steady state from a pressure of 16 lbf/in2 and a temperature of 32oF to a pressure of 50 lbf/in2 and a temperature of 130oF. The gas enters the compressor with a velocity of 30 ft/s and exits with a velocity of 80 ft/s. The mass flow rate is 3500 lb/hr. The magnitude of the heat transfer rate from the compressor to its surroundings is 5% of the compressor power input. Use the ideal gas model with cp = 0.21 Btu/lb·oR and neglect potential energy effects. A.) Determine the flow area at the inlet, in ft2, B.) and the power required by the compressor to work, in horsepower. Show complete solutions.

Refrigerant 134a enters an insulated diffuser as a saturated vapor at 80 deg F with a velocity of 800 ft/s. The inlet area is 1.4 in^2. At the exit, the pressure is 400 lbf/in2 and the velocity is negligible. The diffuser operates at steady state and potential energy effects can be neglected. Determine the mass flow rate, in lb/s, and the exit temperature, in deg F.

Steam enters a turbine operating at steady state with a mass flow rate of 4600kg/h. the turbine develops a power output of 1000kW. At the inlet, the pressure is 60 bar, the temperature is 400°C, and velocity is 10m/s. At the exit, the pressure is 0.1 bar, the quality is 0.9, and the velocity is 50m/s. Calculate the rate of heat transfer between the turbine and surroundings in kW.

Saturated water vapor at 300°F enters a compressor operating at steady state with a mass flow rate of 5 lb/s and is compressed adiabatically to 600 lbf/in.² If the power input is 2150 hp, determine for the compressor: (a) the percent isentropic compressor efficiency and (b) the rate of entropy production, in hp/°R. Ignore kinetic and potential energy effects.

Steam enters a turbine operating at steady state with a mass flow rate 1.28 kg/s. The power output of the turbine is 100kW. The inlet the enthalpy is given as 3177.2 KJ/kg. At the exit the pressure is 10 kPa and the quality is 90%. the change in kinetic energy between the inlet and outlet is negligible. calculate the heat transfer from the turbine to the surroundings

Nitrogen, modeled as an ideal gas, flows at a rate of 3 kg/s through a well-insulated horizontal nozzle operating at steady state. The nitrogen enters the nozzle with a velocity of 20 m/s at 400 K, 400 kPa and exits the nozzle at 100 kPa.To achieve an exit velocity of 500 m/s, determine:(a) the exit temperature, in K.(b) the exit area, in m2.