Engineering Board Exam Reviewer · Thermodynamics · hard
Steam from a 1 MPa line is throttled in a calorimeter to 100 kPa, where its enthalpy is found to be 2716 kJ/kg. At 1 MPa, hf = 762.8 kJ/kg and h fg = 2015.3 kJ/kg. What is the quality of the steam in the line?
- 96.92%
- 97.76%
- 101.79%
- 100.00%
Answer
A. 96.92%
Solution
Throttling: h1 = h2 = 2716 kJ/kg. x = (2716 - 762.8)/2015.3 = 0.9692 = 96.92%.
More Thermodynamics questions
- A wet steam mixture at 200 kPa has a quality of 0.8. If vf = 0.001061 m3/kg and vg = 0.8857 m3/kg, what is its specific volume?
- Steam at 1 MPa has a quality of 90%. If hf = 762.81 kJ/kg and h fg = 2015.3 kJ/kg, what is its enthalpy?
- Wet steam at 100 kPa has an enthalpy of 2000 kJ/kg. If hf = 417.46 kJ/kg and h fg = 2258.0 kJ/kg, what is its quality?
- Two Carnot engines operate in series between 1000 K and 300 K. If both engines produce equal work, what is the intermediate temperature?
- Two Carnot engines operate in series. The first receives heat at 1000 K and the second rejects heat at 300 K. If both engines have equal…
- 1000 kJ of heat is available from a reservoir at 1000 K. If the environment is at 300 K, what is the maximum work (exergy) obtainable from…
- An actual heat engine has a thermal efficiency of 30%, while a Carnot engine between the same reservoirs has an efficiency of 50%. What is…
- A 10-ton refrigeration unit has a refrigerating capacity of approximately:
- A refrigerator removes heat from a cold space at 5 kW with a COP of 2.5. How much heat is rejected to the surroundings?
- A refrigerator removes heat from a cold space at 5 kW with a COP of 2.5. What is the power input required?