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An optimal idle speed control (ISC) system for an automotive engine is introduced in this paper. The system is based on a non-linear model including time delay. This model is linearized at the nominal operating point. The effect of the time delay on control is compensated by prediction. This methodology is applied to a Chrysler 2.0 liter 4-cylinder SOHC (Single Overhead Cam) engine. All of the unknown parameters of the model are identified by using the normal operating data from the test engine. Based on these identified parameters, an optimal controller was designed and implemented using a rapid prototyping system. Numerous experiments of the optimal controller were carried out at the Chrysler Technology Center in Auburn Hills, Michigan. The performance was compared to that of the existing controller. The results showed that the optimal controller has the capability to effectively control the engine idle speed under a variety of accessory loads and disturbances.

In developing the features of a spark-ignition combustion chamber, optical combustion diagnostic technology was employed to understand the factors contributing to knock propensity of the combustion system. This optical combustion visualization equipment utilizes optical prisms located around the periphery of the spark plug shell to measure light intensity of combustion. By synchronizing light intensity and cylinder pressure measurements to crankshaft position, local tracking of combustion progression is accomplished. This method was used to track knock occurrences and to evaluate their controlling parameters within this combustion system. Cylinder head and piston top geometries were developed as a result of this combustion visualization. Recommendations derived from these studies were successfully used to achieve objectives of this engine development program which included improvements in torque and power output, fuel economy, and combustion stability.

Under a contract which began in November 1972, Chrysler Corporation has been conducting an automotive gas turbine improvement program for the Division of Transportation of the Energy Research and Development Administration. The final task of this program is to design, build, and demonstrate an Upgraded Engine. The design been accomplished and is described in this paper. It utilizes a number of improvements developed and verified on the Chrysler Sixth Generation “Baseline” engines, e.g. variable inlet guide vanes, water injection, ceramic regenerators, an integrated electronic control system, a free-rotor arrangement, a low emissions fixed geometry burner, and linerless insulation. Aerodynamic details to meet higher efficiency component specifications were provided by NASA Lewis. The design also incorporates a gas bearing on the rotor and improvements in arrangement and mechanical design.