How Can I Determine the Compressor Exit Temperature?

[thearny]

Product Compression. I am currently doing some work on compression. I know the flowrate in and the pressure and temperature in, and I know the pressure (and flowrate) out. Can I determine the temperature out?

I have tried using P1V1/T1=P2V2/T2, but as V is a function of T (using values from Perry's) I have ended up in iterative cycle in which the exit T is oscillating increasingly wildly with time.

What is the best approach to these calculations?

Thanks in advance.

 

[FredGarvin]

The "best" approach definitely depends on the type of compressor and the process being undertaken.

If you want a place to start, you can look at the T-dS equations for isentropic flow with constant specific heat to come up with:

$$\frac{p_1}{p_2}=\left[\frac{T_1}{T_2}\right]^{\frac{\gamma}{\gamma-1}}$$

 

[oswaler]

I understand your frustration with the iterative cycle you have encountered in trying to determine the compressor exit temperature. One possible approach to these calculations is to use the ideal gas law, which states that pressure, volume, and temperature are interrelated for an ideal gas. In this case, you can use the equation PV=nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is temperature. By rearranging this equation, you can solve for temperature as T=P*V/(n*R).

Additionally, you may want to consider using the isentropic process for compressors, which assumes that the compression is adiabatic and reversible. This can help you to determine the temperature at the exit based on the inlet conditions and the pressure ratio of the compressor. However, keep in mind that this is an idealized model and may not accurately reflect the actual temperature at the exit.

In any case, I would recommend consulting with a thermodynamics expert or using specialized software to accurately calculate the compressor exit temperature. It is important to have precise and reliable data in scientific work, so it is worth investing the time and resources to ensure accurate calculations. Best of luck with your research.