Application of variable geometry turbine turbochargers to gasoline engines- A review

Abstract

An ideal engine today is considered to be one with low emission, low fuel consumption and high specific power output. Engine downsizing by turbocharging provides an answer toall the three. Though the traditional problems of poor low end torque and inadequate transient response have been overcome to a great extent using variable geometry turbine turbocharger in diesel engine, the application of variable geometry turbine turbocharger is in quite a nascent stage when it comes to gasoline engine. This article primarily describes all the important aspects of application of VGTs to gasoline engines right from when VGT’s were restricted to only very expensive research prototypes to the very recent application in cost sensitive production engines. Also at the same time,it highlights the need and development in the flow range of the turbocharger compressor, addressing problems of choke and surge in the turbo chargers compressor.