As shown in the diagram, 15 kg/s of steam enters a de-superheater operating at steady-state at 30 bar and 320oC where it is mixed with liquid water at 25 bar and temperature T3 to produce saturated vapor at 20 bar. Heat transfer between the device and its surroundings and changes in kinetic and potential energies are negligible.
a.) If T3 = 200oC, determine the mass flow rate of stream 3.
b.) Plot the mass flow rate of stream 3 in kg/s as a function of T3 as T3 ranges from 20 to 220oC.
Note that the use of ThermalFluids will avoid the need to interpolate in this problem!
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2 comments:
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HINTS:
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* Set up your solution for part a in a way that it can be easily replicated in part b. (Can use an Excel data table!)
* There are two equivalent ways to solve this problem, depending on how you define your system (control volume). The answer will be the same both ways.
* Remember to also check out the comments from Dr. B's class!
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ANSWERS:
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mass flow rate at 2 = 1.85 kg/s
I reiterate again, please check out the comments from Dr. B's class -- there are some comments on how you can get rid of the multiple unknowns in your first law energy balance by combining it with your mass balance.
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