Self-tuning Gross Heat Release Computation For Internal Combustion Engines

摘要

The paper describes a novel method for self-tuning gross heat release computation in internal combustion engines suitable for both online usage in combustion phasing control applications and postprocessing of cylinder pressure measurements. The method estimates the polytropic exponents and cylinder pressure offsets immediately preceding and succeeding the combustion event, respectively, using a fast nonlinear least-squares method. The polytropic exponent and the pressure offset are subsequently interpolated during the combustion event and a net heat release computation is performed based on the interpolated exponent and pressure. The result is a self-tuning gross heat release algorithm with no need to model heat losses, crevice losses and blow-by explicitly.