Centrifugal Compressor Diffuser Optimization by the Means of DoE Methods and RSM

Centrifugal compressors are broadly implemented in manyindustries because of their ability to handle low andmoderate mass flow rates to obtain high pressure ratios.Design and optimization of compressor components i.eimpeller and vane-less diffuser are considered by manyresearchers as they play an important role in compressorperformance.In this research the vane-less diffuser part of aturbocharger compressor is optimized using design ofexperiment (DOE) technique and response surfacemethodology (RSM). Two different scenarios areconsidered to change diffuser geometry. In the first one, thediffuser discharge width is maintained constant and theinlet section is changed by varying three parameters. Thesecond strategy also changes the discharge section width.Diffuser performance is evaluated through compressorefficiency and pressure ratio and also diffuser pressurerecovery and total pressure loss coefficients. The resultsshow that compressor efficiency and pressure ratio increaseby 2.4% and 2.9% respectively.