PROCESS FOR DETERMINING AND EVALUATING THE COMBUSTION PRESSURE OF AN INTERNAL COMBUSTION ENGINE

摘要

Conventional methods for determining the combustion pressure of an internal combustion engine are very costly and the sensors used must meet stringent requirements. The process described differs from this in that the combustion pressure is calculated by determining the compression pressure pk( alpha ) and measuring the combustion chamber pressure p( alpha ) by means of simple sensors. The combustion pressure p<*>( alpha ) is obtained by subtracting the value of the compression pressure from the combustion chamber pressure. Preferably the variation in compression pressure is obtained by measuring the combustion chamber pressure during compression until the upper dead centre in the working phase is reached and storing the values in a memory. The values of the compression pressure after the upper dead centre is reached are obtained by reflection in an axis passing through the upper dead centre, which results in a symmetrical curve of compression pressure. The combustion pressure can be calculated very easily by this method.