Refrigeration and Air Conditioning Technology (MindTap Course List)
8th Edition
ISBN: 9781305578296
Author: John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson
Publisher: Cengage Learning
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A reheat cycle with two stages of reheating is executed with steam expanding initially from 200 bar (20 Mpaa) and 540 deg C. The 2 reheater pressures are 40 bar (4 Mpaa) and 10 bar (1 Mpaa) and the steam leaves each reheater at 540 deg C. Steam is bled in between two reheating sessions at a pressure equal to 20 and 15 bars into 2 open feedwater heaters. Condensation occurs at 60 deg C. All expansion and compression efficiencies are 90 %. There is a total of 10.3 kg/sec of steam (total mass flow rate m) circulated in the cycle.
Answer the following: fill up the blanks in the items below:
- Equipment layout and TS diagram for the cycle.
- Ideal turbine work (KW) Ans:_______________________________
- Actual mass of steam bled into the open heater m1’= _____________kg/sec for the heater nearest to the SGU/boiler and m2’ = _____________________kg/sec for the heater nearest to the condenser.
- Actual engine efficiency (%) Answer: _______________________
- Actual Rankine cycle efficiency % using Wt’ and Wp’ values Answer: _____________
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