Air at 600 kPa and 500 K enters an adiabatic nozzle that has an inlet - PDF document

1. Air at 600 kPa and 500 K enters an adiabatic nozzle that has an inlet - to - exit area ratio of 2:1 with a velocity of 120 m/s and leaves with a velocity of 380 m/s. Determine (a) the exit temperature and (b) the exit pressure of the air. 2. Steam enters an adiabatic turbine at 8 MPa and 500°C at a rate of 3 kg/s and leaves at 20 kPa. If the power output of the turbine is 2.5 MW, determine the temperature of the steam at the turbine exit. Neglect kinetic energy changes. 3. Liquid water at 300 kPa and 20°C is he ated in a chamber by mixing it with superheated steam at 300 kPa and 300°C. Cold water enters the chamber at a rate of 1.8 kg/s. If the mixture leaves the mixing chamber at 60°C, determine the mass flow rate of the superheated steam required. 4. A thin - walle d double - pipe counter - flow heat exchanger is used to cool oil (cp = 2.20 kJ/kg · °C) from 150 to 40°C at a rate of 2 kg/s by water (cp = 4.18 kJ/kg · °C) that enters at 22°C at a rate of 1.5 kg/s. Determine the rate of heat transfer in the heat exchanger and the exit temperature of water. 5. A 0.3 - m3 rigid tank is filled with saturated liquid water at 200°C. A valve at the bottom of the tank is opened, and liquid is withdrawn from the tank. Heat is transferred to the water such that the temperature in the t ank remains constant. Determine the amount of heat that must be transferred by the time one - half of the total mass has been withdrawn. Look at Lecture 6 Examp les slides for solution..... 6. In a single - flash geothermal power plant, geothermal water enters the flash chamber (a throttling valve) at 230°C as a saturated liquid at a rate of 50 kg/s. The steam resulting from the flashing process enters a turbine and leaves at 20 kPa with a moisture content of 5 percent. Determine the temperature of the steam after the flashing process and the power output from the turbine if the pressure of the steam at the exit of the flash chamber is 1 MPa.