A computational study of compressor surge during transient operation of turbocharged diesel engines

Abstract

The transient response of turbocharged diesel engines is of great importance, especially when compressor surge is likely to occur. Turbocharger compressor surge is a dynamic instability mode that can generate air mass flow rate and pressure rise oscillations of large amplitude, and may also induce severe torsional loading to the turbocharger shaft. In this paper, an effort is made to study by simulation the effect of various parameters on the compressor surge behaviour. By varying these parameters, it can be revealed how compressor surge is affected and how surge intensity is influenced. To this aim, a simulation program developed is used for transient operation runs, which are critical for surge appearance. This has been applied on a six-cylinder, diesel engine of marine duty. The model has a control-design oriented philosophy and is capable of identifying the impact of each parameter on compressor surge. Thus, it can prove a useful tool to the engine designer.