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Cylinder deactivation has been proposed so far for improved part load operation of large gasoline engines. In all this application, the cylinder deactivation has been achieved keeping the intake and exhaust valves closed for a particular cylinder, with pistons still following their strokes. The paper presents a new mechanism between the piston and the crankshaft to enable selective deactivation of pistons, therefore decoupling the motion of the piston from the rotation of the crankshaft. The reduced friction mean effective pressure of the new technology enables the use of piston deactivation in large engines not necessarily throttle controlled but also controlled by quantity of fuel injected. Results of performance simulations are proposed for a HSDI V8 engine, producing significant savings during light operation.

Turbocharging dramatically improves the power density of internal combustion engines both in the compression ignition and the spark ignition cases. However, a standalone turbocharger suffers from transient and steady state downfalls where the energy to turbine is either smaller or larger than what would be needed to optimize the engine operation in a specific steady state or transient point. Hence a concept was proposed of a super-turbocharger where the turbocharger shaft is connected to the crankshaft through a continuously variable transmission and a gear. Energy is drawn from the crankshaft or delivered to the crankshaft to improve the work in every operating point of the steady map. In this paper, the concept of super-turbocharger is applied to a six-cylinder, dual fuel diesel injection ignition engine. The system is modelled using state-of-the-art automotive software and simulations of the steady-state operation are presented.

In this paper, the concept of super-turbocharging is applied, in simulation, to a four-cylinder direct injection jet ignition gasoline engine. Turbocharging improves the power density of internal combustion engines, both the compression ignition and the spark ignition. However, a standalone turbocharger suffers from transient and steady state performance and efficiency degradation where the energy to turbine is either smaller or larger than what would be needed to optimize the engine operation in a specific point. Hence a concept is proposed to use a super-turbocharger, where the turbocharger shaft is connected to the crankshaft through a continuously variable transmission (CVT) and a gears pair. Energy is drawn from the crankshaft or delivered to the crankshaft to better work in every operating point. The concept was originally proposed for a diesel engine. Here it is applied to a gasoline engine.

The paper discusses the benefits of a four stroke engine having one intake and one exhaust rotary valve. The rotary valve has a speed of rotation half the crankshaft and defines an open passage that may permit up to extremely sharp opening or closing and very large gas exchange areas. The dual rotary valve design is applied to a racing engine naturally aspirated V-four engine of 1000cc displacement, gasoline fuelled with central direct injection and spark ignition. The engine is then modeled by using a 1D engine & gas dynamics simulation software package to assess the potentials of the solution. The improved design produces much larger power densities than the version of the engines with traditional poppet valves revving at higher speeds, with reduced frictional losses, and with larger gas exchange areas while also improving the fuel conversion efficiency thanks to the sharpness of opening or closing events.