Engineering, 03.04.2021 03:10 kirstennnash
Consider the compression step of an ordinary vapor compression cycle using ammonia as the working fluid. The inlet to the compressor is saturated vapor at 10 C and approximately 6.25 bar, the outlet is superheated vapor at 10 bar. Approximate the non-ideal PVT-behavior of ammonia in this region by the van der Waal’s EOS. Using the data Tc = 132.4 C, Pc=112.8 bar, and Cv=36.1 kJ/kmol-K (and no other data), derive a set of equations that can be solved simultaneously for the temperature of the outlet stream, assuming the compressor is reversible. Clearly define the set of unknown variables to be solved for in your equations in addition to the outlet temperature. Be sure that your system is ‘square’; i. e., has the same number of independent equations as unknowns. Note that to be solvable your equations must be purely ‘algebraic’–there may not be any unsolved integral terms remaining. Comment on whether or not your equations have a unique solution, and how you would check that a solution found numerically is the correct solution.
Answers: 3
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Answers: 3
Consider the compression step of an ordinary vapor compression cycle using ammonia as the working fl...
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