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

•The behavior of a turbocharger for heavy duty vehicle application was studied.•A broad experimental activity was developed under steady flow condition.•Compressor performance was analyzed in unstable zone over an extended range.•The definition of surge line position is shown adopting different methods.•Maps can help simulation model to accurately predict engine performance.

To make simulation models able to accurately predict engine performance, a better understanding of compressor behavior over an extended range can be accomplished by using a 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 both in the stable and unstable operating region.