Evaluation and Selection of Turbocharger Meeting BS6 Emission Norms for 1.99l Engine

Migration to BS6 emission norms from BS4 levels involves strenuous efforts involving advanced technology and higher cost. The challenging part is on achieving the stringent emission norms without compromising the engine fuel economy, performance and NVH factors. Selection of hardware and attaining an optimal behaviour is therefore vital. This article focuses on the evaluation of three different configuration of turbochargers for the same engine to meet the BS6 emission norms and performance. The turbocharger samples used measure the same compressor diameter with varying trim ratios. Simulation and testing of turbochargers ensured positive results for confirmation of the system. Parameters like low speed torque, smoke and compressor efficiency were evaluated and analysed for all configurations. The safe limits of surge and choke regions of all the compressors were also studied and verified. Influence of varying compressor trim on the performance and emissions were examined thoroughly in this work. Full throttle performance and 14 mode test for emissions concluded that the performance and emission parameters were satisfactory with all the turbochargers. However, 4778 Turbocharger gives best Full load performance than other Turbochargers and meeting the 14 mode emission target and it’s finally selected for the engine application.