8.56. Humid air at 70°C and 1.0 atm with 6°C of superheat is fed to a...

8.56. Humid air at 70°C and 1.0 atm with 6°C of superheat is fed to a condenser. Gas and liquid streams leave the condenser in equilibrium at 25°C and 1 atm. (a) Assume a basis of calculation of 100 mol inlet air, draw and label a flowchart (including Q in the labeling), and carry out a degree-of-freedom analysis to verify that all labeled variables can be determined. (b) Write in order the equations you would solve to calculate the mass of water condensed (kg) per cubic meter of air fed to the condenser. Circle the unknown variable for which you would solve each equation. Do not do any of the calculations. (c) Prepare an inlet–outlet enthalpy table, inserting labels for unknown specific enthalpies (H^1, H^2, . . .). Write expressions for the labeled specific enthalpies, substituting values or formulas for heat capacities and latent heats but not calculating the values of the specific enthalpies. Then write an expression for the rate at which heat must be transferred from the unit (kJ per cubic meter of air fed to the condenser). (d) Solve your equations by hand to calculate kg H2O condensed/m3 air fed and kJ transferred/m3 air fed. (e) What cooling rate (kW) would be required to process 250 m3 air fed/h?

Expert Solution

Amanda K answered 2 years ago

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