Method of determining fluctuations in indicated mean effective pressure of engine and apparatus therefor

摘要

A method of and an apparatus for measuring fluctuations in the indicated mean effective pressure of an engine from a deviation of the mean pressure or from an unbiased variance (mean square) of the mean pressure obtained from the deviation in the mean pressure by utilizing a deviation of the mean pressure becomes substantially identical with a deviation of the indicated mean effective pressure or an unbiased variance (mean square) of this mean pressure becomes substantially identical with an unbiased variance (mean square) of the indicated mean effective pressure in a cylinder of the engine. This deviation of the mean pressure is calculated from detected changes in the rotational speed of the engine.