Study of the Losses in Fluid Machinery with the Help of Entropy

Martin Böhle (1) , Annika Fleder (1) , Matthias Mohr (1)

1 TU Kaiserslautern - Technical University of Kaiserslautern

In the current design process of turbomachinery the use of CFD methods is state of the art. With CFD calculations we are able to predict the performance characteristics of the machines. In most of the cases the machines are rated based on their performance alone. A detailed evaluation of the losses involved often is not conducted, mainly because there is no established method to analyze the location and mechanisms of loss production. This leads to the fact that the loss mechanisms for some turbo machines are not known in detail, although they are very important to completely understand the operation principle of the machines and have a huge influence on their performance. If the location and quantity of losses were known, it would be possible to perform a selective optimization of the machine. The question is just how to calculate and localize the losses and evaluate them with CFD. In his thesis Kock introduces a method, to identify losses in CFD. His method is based on the entropy production rates in turbulent flow fields. In this paper the method is applied on hydraulic fluid machinery and two different machine types are discussed in detail. Those are a side channel pump and an inducer. The locations of the losses are detected and the size of losses will be evaluated by applying the method of Kock.

Domaines: Mécanique [physics]

Martin Böhle, Annika Fleder, Matthias Mohr. Study of the Losses in Fluid Machinery with the Help of Entropy. 16th International Symposium on Transport Phenomena and Dynamics of Rotating Machinery, Apr 2016, Honolulu, United States. ⟨hal-01879371⟩