Normally, the thermodynamic calculations are performed for an ideal (reversible process). Reference emphasizes that using a single value for each variable is not the correct way to evaluate a compression system. Thus the most difficult part of a compressor calculation is specification of a reasonable range for each variable and not the calculation itself. A compressor is going to operate under varying values of the variables affecting its performance. Gas composition is important but a small error here is less important providing it does not involve the erroneous exclusion of corrosive components. Where mass flow rate and h is specific enthalpy.įrom a calculation viewpoint alone, the power calculation is particularly sensitive to the specification of flow rate, inlet temperature and pressure, and outlet pressure.
The theoretical power requirements are independent of compressor type the actual power requirements vary with the compressor efficiency. The results indicate that the accuracy of the shortcut method is sensitive to the value of heat capacity ratio, k. The enthalpies and entropies are used to determine the power requirement and the discharge temperatures.
The rigorous method is based on an equation of state like the Soave-Redlich-Kwong (SRK) for calculating the required enthalpies and entropies. We will compare the rigorous method results with the values from the short cut methods. In this tip of the month (TOTM) we will present the compressor calculations of a case study.
0 kommentar(er)
