TechTalk - Modelling to Predict the Performance of Positive Displacement Compressors

7 Feb 2019

groll cooling2

Download the Paper 

PDSim: A Generalized Modeling Platform to Predict the Performance of Positive Displacement Compressors

Listen to the Webinar

Access the the webinar here


In this talk and paper Eckhard will present his J&E Hall Gold Medal Award winning research. He has been working on the modelling and testing of positive displacement compressors for more than twenty years. Detailed and comprehensive simulation models of hermetic, semi-hermetic and open-drive positive displacement compressors, including scroll, rotary, reciprocating, spool, Bowie, Z-compressor, and S-RAM among others, have been developed throughout the years and validated against experimental compressor measurements. These models were also used to perform parametric studies where the influences of compressor geometry, leakage gaps, heat transfer coefficients and frictional coefficients on performance were investigated.

This presentation describes a new comprehensive compressor simulation platform based on the previous compressor modeling efforts to predict the performance of positive displacement compressors.  The platform include all of the main aspects of compressor modeling, such as the geometry (a library of multiple positive displacement compressor geometries has been programmed), the thermodynamic governing equations, i.e., energy and mass balances for the compression process, internal leakage paths, suction and discharge valve dynamics, internal heat transfer, friction and mechanical losses as well as electric motor losses.

The generic model platform has been validated using external compressor performance measurements, which are readily available from the previous testing efforts with various compressors and refrigerants using hot gas-bypass compressor load stands and a calorimeter.

The ability of the PDSim modeling platform to accurately predict the performance of hermetic positive displacement compressors will be discussed in detail.


What you will learn

  • To understand the working mechanisms of positive displacement compressor, such as reciprocating, scroll and rolling piston compressors
  • To understand the concept of generalized positive displacement compressor simulation models.
  • To be familiar with core elements of compressor simulation, such as control volumes, flow paths, leakages, friction, heat transfer, and state properties.
  • To learn the basic and advanced aspects of modelling positive displacement compressors.
  • To understand how to use these models to evaluate design changes via parametric studies.



Dr. Eckhard Groll was the winner of the IOR's J&E Hall Gold Medal for innovation. He works as Reilly Professor of Mechanical Engineering and also serves as the Associate Dean for Undergraduate and Graduate Education in the College of Engineering at Purdue University.  He joined Purdue University as an Assistant Professor in 1994 and was promoted to Associate Professor in 2000, to Full Professor in 2005, and to the Reilly Professorship in 2013.  He received his Diploma in Mechanical Engineering from the University of the Ruhr in Bochum, Germany, in 1989 and a Doctorate in Mechanical Engineering from the University of Hannover, Germany, in 1994.  



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