The Dynamic Transfer Characteristics of Reciprocating Engines

Abstract

The methods of sampled data analysis and small perturbation techniques are used to predict the dynamic characteristics of reciprocating engines. Extensive frequency response tests have been carried out on a compression ignition engine to determine the engine dynamic characteristics and the results agree well with the theoretical predictions. A method of plotting the results is suggested which has the advantage of generality and takes into account engine speed changes and load torque-speed characteristics. The experimental methods used involve the use of electro-hydraulic systems. These have great advantages for providing the appropriate input and loading conditions. Whilst the main body of the report is concerned with the theory and testing of compression ignition engines, the methods suggested can be applied equally well to petrol engines.