Question

In: Other

An ammonia heat engine has the following reversible steps: 1 ? 2 Isothermal heating of saturated...


An ammonia heat engine has the following reversible steps:

1 ? 2 Isothermal heating of saturated liquid @ 60°C to superheated vapor

2 ? 3 Adiabatic expansion to saturated vapor at -20°C

3 ? 4 Isothermal cooling to a 2 phase fluid

4 ? 1 Adiabatic compression back to state 1

Find QH (in kJ/kg). Use the correct sign convention to indicate the direction of heat. Hint: build a T-S diagram of the whole cycle first.

Solutions

Expert Solution


Related Solutions

Select the best engine in term thermal efficiencies of an actual and reversible heat engine of two heat engine given below and give reason for your selection
  Select the best engine in term thermal efficiencies of an actual and reversible heat engine of two heat engine given below and give reason for your selection Engine A:-Source temperature 800K, heat input rate 450 kW, heat rejection rate 300 kW, sink temperature 315K Engine B:-Source temperature 650K, heat input rate 345 kW, pumping power 5 kW, turbine power 120 kW, sink temperature 300K.
Which one has a larger final entropy, reversible isothermal process or reversible adiabatic process when expanding...
Which one has a larger final entropy, reversible isothermal process or reversible adiabatic process when expanding to the same final volume for an ideal gas? What do you assume the entropy S for a perfect crystal when T = 0? Is the S(0) still zero if the crystal is not perfect? Why? How to calculate dS when under the constant pressure and cp is given? How to calculate the entropy of H2O at 500 K? How to calculate the entropy...
9. Which of the following statements is FALSE? I. The efficiency of a heat engine has...
9. Which of the following statements is FALSE? I. The efficiency of a heat engine has no units II. The coefficient of performance of a heat pump has no units III. The coefficient of performance can be less than 1 IV. The Carnot efficiency of a heat engine can be increased by decreasing the temperature difference between the cold and hot reservoir a. I and II b. II and III c. Only III d. III and IV e. II and...
2. Understand how much work and heat are transferred in an ideal heat engine or reverse...
2. Understand how much work and heat are transferred in an ideal heat engine or reverse heat engine. a) What is the maximum work that I can get from a heat source at 450K and a cold sink at 298K? (0.338 J per joule of heat in at 450 K) b) How much heat can I get from ideal reverse heat engine per Joule of energy of work if the outside temperature is 10oC and my house is at 25oC?...
(1) Derive all thermodynamic parameters (dH, dU, dw, dq and dS) for an isothermal reversible expansion/compression...
(1) Derive all thermodynamic parameters (dH, dU, dw, dq and dS) for an isothermal reversible expansion/compression at (a) isothermal , (b) isochoric and (c) isobaric conditions. Also draw relevant PV diagram and highlight work-done during each process. Thank you!!
A heat engine uses a heat source at 580 ∘C and has an ideal (Carnot) efficiency...
A heat engine uses a heat source at 580 ∘C and has an ideal (Carnot) efficiency of 29 % . To increase the ideal efficiency to 46 % , what must be the temperature of the heat source?
A piston-cylinder heat engine has five kilograms of air as the working fluid. Analyze this engine...
A piston-cylinder heat engine has five kilograms of air as the working fluid. Analyze this engine as a Carnot engine and determine the work of expansion and the amount of heat rejected in KJ assuming constant specific heat at 300k. During the heat rejection, the temperature is 300?. There is a temperature difference of 600 degrees in the engine. At the beginning of the heat rejection process, the pressure is .2MPa and during heat addition the volume doubles. Draw the...
A heat engine made with an ideal gas with f = 5 degrees of freedom has...
A heat engine made with an ideal gas with f = 5 degrees of freedom has 3 steps. Starting with a volume of 8 liters and a pressure of 1.3 × 10^5 Pa, the gas is compressed adiabatically to a volume of 1 liter and a pressure P2. Next the gas expands at constant pressure back to 8 liters, then the pressure drops at constant volume back to 1.3×10^5 Pa. Draw the cycle in a P −V diagram. Calculate the...
A heat engine made with an ideal gas with f = 5 degrees of freedom has...
A heat engine made with an ideal gas with f = 5 degrees of freedom has 3 steps. Starting with a volume of 8 liters and a pressure of 1.3 × 10^5 Pa, the gas is compressed adiabatically to a volume of 1 liter and a pressure P2. Next the gas expands at constant pressure back to 8 liters, then the pressure drops at constant volume back to 1.3×10^5 Pa. Draw the cycle in a P −V diagram. Calculate the...
NASA has created a heat engine which operates between the sun and the vacuum of the...
NASA has created a heat engine which operates between the sun and the vacuum of the space where the temperature is absolute zero. He says that his engine is nearly 100% efficient. Do you agree with the claim assuming the engine to be totally reversible? Analyse the scenario using equation for efficiency of Carnot engine and Kelvin statement to evaluate your conclusion.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT