Thermodynamic Analysis of the Diabatic Efficiency of Turbines and Compressors

- Journal title : Transactions of the Korean Society of Mechanical Engineers B
- Volume 40, Issue 3, 2016, pp.139-148
- Publisher : The Korean Society of Mechanical Engineers
- DOI : 10.3795/KSME-B.2016.40.3.139

Title & Authors

Thermodynamic Analysis of the Diabatic Efficiency of Turbines and Compressors

Park, Kyoung Kuhn;

Park, Kyoung Kuhn;

Abstract

Thermodynamic analysis is conducted on the first-order approximation model for turbines and compressors. It is shown that the adiabatic efficiency could be greater than unity, depending on the entropic mean temperature, entropy generation, thermal reservoir temperature, and heat transfer. Therefore, adiabatic efficiency applied to a diabatic control volume results in an error overestimating its performance. To resolve this overestimation, it is suggested that a reversible diabatic process be referred to as an ideal process to evaluate diabatic efficiency. The diabatic efficiency suggested in this work is proven to always be less than unity and it is smaller than the exergy efficiency in most cases. The diabatic efficiency could be used as a more general definition of efficiency, which would include adiabatic efficiency.

Keywords

Adiabatic Efficiency;Diabatic Efficiency;Exergy Efficiency;Turbine;Compressor;Diabatic Process;

Language

Korean

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