Design of High Efficiency Compressors with Low GWP Refrigerants

Refrigerants are used in many applications such as stationary and mobile air conditioning and refrigeration systems. A commonly used refrigerant such as R134a has a low Ozone Depleting Potential (ODP) but relatively high Global Warming Potential (GWP) of 1400. In recent years there has been substantial growth in refrigerant used for cooling applications.

small-heat-pump-compressor

For example, between 2002 and 2010 the refrigerant used has grown from 450 M Tonnes to almost 1100 M Tonnes of CO2 equivalent. This rate of growth is expected to continue to increase as a result of new applications such as domestic heat pumps and Organic Rankine Cycles. As a result, the EU has introduced legislation to phase out the use of high GWP refrigerants such as R134a by 2030. R134a has already been banned from mobile (automotive) applications in Europe and are being incentivised out in the US. The use of low GWP refrigerants such as R1233zd has major implications on the design of compressors.

In our webinar, we show how using the different modules in TURBOdesign Suite you can design high efficiency compressors rapidly from scratch. We use an example of a small heat pump and show the following design process:

Creation of real gas property tables (RGP) from REFPRO for the new refrigerant.
Meanline design of the compressor by using TURBOdesign Pre and the RGP files.
3D design of the impeller by TURBOdesign1.
Optimization of the impeller geometry for multiple operating points by TURBOdesign Optima.