Thermodynamics compressor Question

AI Thread Summary
The discussion revolves around a thermodynamics problem involving a compressor where air enters at specific conditions and exits at a higher pressure. Key calculations include determining the exit temperature, the diameter of the exit pipe, and the isentropic efficiency of the compressor. Participants emphasize the importance of showing work to facilitate assistance and clarify the relationships between temperature and pressure in a polytropic process for an ideal gas. Additionally, the mass flow rate of air entering and leaving the compressor is highlighted as a critical factor. The conversation underscores the need for adherence to forum rules regarding posting and providing sufficient problem-solving details.
Jason Brooks
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Homework Statement



Air enters a compressor operating at a steady state with a pressure of 14.7 psi, a temperature of 70 F , and a volumetric flow rate of 500 ft^3/min. The air velocity in the exit pipe is 700ft/s and the exit pressure is 120 psi. If each unit mass of air passing from the inlet to the exit undergoes a process described by pv^1.34= constant determine the exit temperature on F and the diameter of the exit pipe in inches. What is the isentropic efficiency of the compressor?


Homework Equations





The Attempt at a Solution

 
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Jason, Welcome to the PF, but do NOT post multiple threads with the same question in other forums. I've deleted the two other copies of this question, and left this one here in the homework forum where it belongs. You are also receiving a warning via the PF warning system.

You also need to show your work so far in order for us to help you (PF rules).
 
I moved this thread to the Intro Physics homework forum where it will probably get more looks. Jason -- you still need to post some work for us to help you.
 
Part 1: What can you say about relationships between temperature and pressure in a polytropic process for an ideal gas?

Part 2: What can you say about the mass flow rate of air entering and leaving the compressor?
 
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