Chapter 7, Problem 7.36P

Thermodynamics, please show all work. Step 1 and 2.

Determine the change in exergy in kJ for each of the following processes in the system with 1 kg of steam at 20 bar and 240 °C initially. a) In case the system is heated to double its volume at constant pressure. b) In case of expansion by doubling the system volume isothermally. dead state; T0=20 °C, P0=1 bar

Steam enters a counterflow heat exchanger operating at steady state at 0.07 MPa with a quality of 0.9 and exits at the same pressure as saturated liquid. The steam mass flow rate is 1.7 kg/min. A separate stream of air with a mass flow rate of 100 kg/min enters at 30°C and exits at 60°C. The ideal gas model with c, = 1.005 kJ/kg-K can be assumed for air. Kinetic and potential energy effects are negligible. Determine the temperature of the entering steam, in °C. For the overall heat exchanger as the control volume, what is the rate of heat transfer, in kW.

Steam enters a counterflow heat exchanger operating at steady state at 0.07 MPa with a quality of 0.9 and exits at the same pressure as saturated liquid. The steam mass flow rate is 1.6 kg/min. A separate stream of air with a mass flow rate of 100 kg/min enters at 30°C and exits at 60°C. The ideal gas model with c, = 1.005 kJ/kg-K can be assumed for air. Kinetic and potential energy effects are negligible. Determine the temperature of the entering steam, in °C. For the overall heat exchanger as the control volume, what is the rate of heat transfer, in kW. Step 1 Your answer has been saved. See score details after the due date. Determine the temperature of the entering steam, in °C. T, = 90 °C Attempts: 1 of 1 used Step 2 For the overall heat exchanger as the control volume, what is the rate of heat transfer, in kW. = i kW Save for Later Attempts: 0 of 1 used Submit Answer

A domestic water heater holds 189 L of water at 60°C, 1 atm. Determine the exergy of the hot water, in kJ. To what elevation, in m, would a 1000-kg mass have to be raised from zero elevation relative to the reference environment for its exergy to equal that of the hot water? Let To = 298 K, po = 1 atm, g = 9.81 m/s².

Steam enters a counterflow heat exchanger operating at steady state at 0.05 MPa with a quality of 0.9 and exits at the same pressure as saturated liquid. The steam mass flow rate is 1.7 kg/min. A separate stream of air with a mass flow rate of 100 kg/min enters at 30°C and exits at 60°C. The ideal gas model with c, = 1.005 kJ/kg-K can be assumed for air. Kinetic and potential energy effects are negligible. Determine the temperature of the entering steam, in °C. For the overall heat exchanger as the control volume, what is the rate of heat transfer, in kW. Step 1 Your answer has been saved. See score details after the due date. Determine the temperature of the entering steam, in °C. T1 = 81.317 °C Attempts: 1 of 1 used Step 2 For the overallI heat exchanger as the control volume, what is the rate of heat transfer, in kW. kW Save for Later Attempts: 0 of 1 used Submit Answer

A steam turbine at steady state is operated at part load by throttling the steam to a lower pressure before it enters the turbine. Before throttling, the pressure and temperature are, respectively, 1.5 MPa and 320°C. After throttling, the pressure is 1 MPa. At the turbine exit, the steam is at .08 bar and a quality of 90%. Heat transfer with the surroundings and all kinetic and potential energy effects can be ignored. Determine. (a) the temperature at the turbine inlet, in °C, and (b) the power developed by the turbine, in kJ/kg of steam flowing.

A steam turbine at steady state is operated at part load by throttling the steam to a lower pressure before it enters the turbine. Before throttling, the pressure and temperature are, respectively, 1.5 MPa and 320°C. After throttling, the pressure is 1 MPa. At the turbine exit, the steam is at .08 bar and a quality of 90%. Heat transfer with the surroundings and all kinetic and potential energy effects can be ignored. Determine. (a) the temperature at the turbine inlet, in °C, and (b) the power developed by the turbine, in kJ/kg of steam flowing.

answer 99 and 100