AN INNOVATIVE METHOD FOR DETERMINING MAXIMUM POWER OBTAINABLE FROM A COMMON RAIL TURBOCHARGED DIESEL ENGINE STARTING FROM EXPERIMENTAL DATA

This paper presents an experimental method for determining the maximum powerobtainable from an aircraft diesel engine derived from the automotive field. Severaltests were performed to estimate the real values of pressure and thermal loads on thepiston and head. The simple and original method described in this paper made itpossible to define two constants for the description of the engine-performanceenvelope.Maximum allowable pressure on the piston and the head was evaluated withcomputer simulation. Two different indicator cycles of the same engine (in theautomotive and aircraft version) were analyzed to extrapolate three constants thatdefine the engine family:• The contributing factor of compression (the exponent of the polytrophic curve n)• The contributing factors of combustion (a constant and an exponent)These contributing factors were examined and quantified separately.The paper is composed of two parts: the first part highlights the ultimate loads oncritical engine parts while the second details the method for the extrapolation of theultimate power output value. Successive experimental tests performed on the engineconfirmed the simple method described herein.