Experimental analysis on the performance of a turbocharger compressor in the unstable operating region and close to the surge limit

To make simulation models able to accurately predict engine performance, a better understanding of compressor steady flow performance over an extended range must be accomplished thanks to the availability of specialized test facility and measuring equipment. Besides, the correct surge line position is another important aspect to be considered to optimize engine-turbocharger matching calculation. In the paper the results of an experimental investigation developed on a turbocharger compressor for heavy duty vehicle application is presented. The study was focused on the definition of surge line position adopting different methods and on the evaluation of compressor performance over an extended range, taking into account compressor behavior in stable and unstable region.