This paper provides design and test data on a crankshaft driven hydraulic system for adding auxiliary energy to the compressor power input of an exhaust gas turbocharger during truck engine acceleration under load, or during heavy “lug-down” operation. The system is applicable to 2 or 4 stroke engines. With a 2 stroke engine the system allows the turbocharger to replace the conventional crankshaft driven scavenge blower even at start-up.
Critical exhaust smoke is significantly reduced both in intensity and in duration, and the engine rev/min at which peak torque occurs can be lowered by 10 to 15% of the speed range.
The hydraulic system comprises a high pressure gear type pump which is driven from the engine crankshaft, through a suitable clutch, and transfers energy to the turbocharger shaft by way of a simple nozzle jetting engine sump oil, at high velocity, on to the buckets of a miniature Pelton wheel turbine, about 35 to 50 mm in diameter.