A Comparison between Experimental and Analytical Transient Test Results for a Turbocharged Diesel Engine

A computer controlled diesel engine test-bed is described. The system is capable of excursions into regions of very low air-fuel ratio operation without damage to the engine; this enables the engine "steady-state" characteristics to be measured for off-design operating conditions. A computer-based data acquisition system was developed to acquire test-bed results under engine transient operating conditions. An analogue computer model of the engine was constructed using the steady-state characteristics of the engine as obtained from on- and off-design. This model operated in real-time and was suitable for both studies of engine control systems and the testing of control hardware. Results obtained from the test-bed and the model are compared. It is shown that good agreement can be achieved by minor modifications to the model based on steady state results. /Author/TRRL/