Development of a Broad Range Turbocharger using Compressor-to-Turbine Bleed 820327
A turbocharger, incorporating bleed flow from the compressor to the turbine, was developed towards the objective of improving the lug performance of the Army's VHO diesel engine, without the complexity of variable geometry diffuser vanes.
An existing VHO engine turbocharger was redesigned and modified for bleed flow testing. The bench and engine test results indicated that the configuration bleeding from both the diffuser hub and the diffuser vane suction surface gave over 75% improvement in baseline engine lug torque. In addition, the bleed flow turbocharger gave improved engine BSFC, with a measured value of less than .39 lb/bhp hr. The lug torque improvements were obtained while maintaining rated engine power.
The results of this program indicate that the bleed flow turbocharger can give significant improvements in lug engine performance without the complexity of variable geometry diffuser vanes.