Performance and emission enhancements of a variable geometry turbocharger on a heavy-duty diesel engine

Abstract

Variable Geometry Turbochargers (VGTs) have emerged in the heavy-duty diesel market with the simultaneous introduction of Exhaust Gas Recirculation (EGR) in meeting emission standards. From a military perspective, VGTs offer considerable promise of improving low speed torque and overall fuel economy. Despite these gains, nitric oxides (NOx) emissions generally increase with increased boost. During times when the military can reduce its environmental impact, VGTs can drive EGR and counter the increase in NOx emissions with relatively minor penalty in particulate matter (PM) emissions. This study highlights the performance and emission enhancements enabled by a VGT on a heavy-duty diesel engine.