Find the Exit Temperature of the Air in the Compressor

AI Thread Summary
To find the exit temperature of air in the compressor, the problem involves applying the first law of thermodynamics for a control volume. Given the inlet conditions of pressure, temperature, and volumetric flow rate, along with the exit pressure and heat transfer rate, the equation Qcv + m'1(h1) = m'2(h2) + Wcv can be utilized. The heat transfer rate is specified as 9.7 Btu per lb of air, and the power input is 90 hp. The challenge lies in determining the mass flow rate and specific enthalpy values to solve for the exit temperature. Ultimately, applying these principles will yield the desired exit temperature in °F.
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Homework Statement


Air enters a compressor operating at steady state with a pressure of 14.7 lbf/in2, a temperature of 80°F and a volumetric flow rate of 18 ft3/s. The air exits the compressor at a pressure of 90 lbf/in2. Heat transfer from the compressor to its surroundings occurs at a rate of 9.7 Btu per lb of air flowing. The compressor power input is 90 hp. Neglecting kinetic and potential energy effects and modeling air as an ideal gas, determine the exit temperature in °F.


Homework Equations





The Attempt at a Solution



I suspect that I need to use:

Qcv+m'1(h1+v21/2) = m'2(h2 + v22/2) + Wcv

Is Qcv = 9.7 Btu/lb and Wcv= 90 hp?
 
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