Half/Full Toroidal, Single/Double Roller, CVT Based Transmission for a Super-Turbo-Charger

Abstract

Turbocharging dramatically improves the power density of internal combustion engines. However, when the energy to turbine is either smaller or larger than what is needed by the compressor for a specific steady state or transient point, there are downfalls, such as turbo-lag, lack of boost, or wasted exhaust energy. Here we propose a super-turbo-charger, where the turbo-charger shaft is connected to the crankshaft through a continuously variable transmission (CVT) and gears’ pairs. Different designs are considered, half-toroidal and full-toroidal, single-roller or double-roller, single-CVT or two-CVT-in-series. Energy is drawn from the crankshaft or delivered to the crank-shaft to improve the steady or transient operation. In this paper, a six-cylinder, dual fuel diesel injection ignition engine is super-turbocharged. Engine performance simulations show the opportunity to achieve a nearly flat maximum torque all over the range of engine speeds and very high efficiencies from one fourth of the load up-wards.