The Development of New Evaluation Criteria for Supercharged Engines Based on Elasticity and Adaptability at Traction

Abstract

This paper aims to outline supercharged engines from the perspective of elasticity and adaptability, starting with the curves of power and torque. As is already known, the diagram of supercharged engine is not similar with the one of natural aspirated engine. As a result, classic coefficients are not suitable for this type of engines, because they can’t define in a proper way how the engine is running. Beginning with the particularities of the supercharged engine, in the paper are defined new coefficients which allows to appreciate in a correct way the engine behavior on the vehicle. As a result, are defined the following coefficients: the coefficient of torque diagram flattening, the coefficient of power diagram flattening, the coefficient of stability, the coefficient of instability, the coefficient that define the field of use, the coefficient of adaptability, the coefficient of elasticity, the coefficient of torque reserve, the coefficient of power reserve. Using these coefficients, the authors defined an equation of optimization, termed equation of efficiency, which allows to evaluate in a global way a wide variety of supercharged engines.