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This study describes the design and proof-of-concept testing of a system which has enabled sub-zero cold starting of a port-injected V6 engine fuelled with M100. At -30°C, the engine could reach running speed about 5s after the beginning of cranking. At a given temperature, starts were achieved using a fraction of the mixture enrichment normally required for the more volatile M85 fuels. During cold start cranking, firing is achieved using a high energy plasma jet ignition system. The achievement of stable idling following first fire is made possible through the use of an Exhaust Charged Cycle (ECC) camshaft design. The ECC camshaft promptly recirculates hot exhaust products, unburnt methanol and partial combustion products back into the cylinder to enhance combustion. The combined plasma jet/ECC system demonstrated exceptionally good combustion stability during fast idle following sub-zero cold starts.

Preliminary test results are presented for an S.I. engine which used a focused laser beam and conventional spark ignition as ignition sources. The results show that for a steady running single-cylinder engine with MBT spark timing and fixed throttle position, engine performance and efficiency are improved, extension of the lean limit of operation by 5 air-fuel ratios is possible, and more NO is produced with laser ignition. The effects of EGR are also examined. The CO and HC emissions are essentially the same. With the laser, the spark location was found to have little effect on performance except when it was moved near the combustion chamber wall. The minimum laser pulse energy required for steady engine operation seems to be dictated by the minimum energy required to achieve breakdown of the laser pulse in air at the same pressure.

A timed high energy spark discharge system was used as an aid for low temperature starting of two single cylinder, and one multi-cylinder Diesel engines. The tests were conducted by cold soaking the engines in a low temperature chamber in temperatures down to −55°C. An Arctic (AA) Diesel fuel was used at these low temperatures while '(Ho 2) fuel was used at warmer temperatures. When used in I.D.I, engines the timed spark discharge system produced more rapid starts and faster warm ups at lower temperatures and consumed equal or less electrical energy when compared to the factory fitted electric glow plugs. An in cylinder glow plug, which was fitted to a D.I. engine, but is not a factory option, produced more rapid starts than the timed spark discharge, but the timed spark system produced smoother running and consumed only one-half the electrical energy.

The use of cylinder pressure transducers in engine control systems will permit optimum performance under all operating conditions. Previous research has shown that it is possible to automatically detect and evaluate knocking combustion based on low frequency (1 point per crank angle degree) pressure data from research and production engines. However, the previous work was done in a single cylinder research engine and a production engine with relatively slow combustion and large knock pressure peaks. In this study, a spark-plug-mounted pressure transducer and an in-cylinder flush mounted pressure transducer were used to monitor the combustion pressure in a modern four cylinder engine during knocking and normal full load operation over a speed range of 1800 RPM to 4000 RPM. This engine features much more rapid combustion and much smaller knock pressure peaks.

In a previous paper, a knock indicator based on the third derivative of the cylinder pressure trace has been developed. This knock indicator measures the rate at which pressure trace curvature changes from positive to negative during the knock peak. Since it is dealing only with the general shape of the pressure trace, it gives a measurement of combustion severity based on low frequency data such as is commonly used for engine cycle analysis. This low frequency sampling makes it useful for adding knock analysis to existing engine analysis programs without changes of equipment or significant increases in computational effort. It may also make it useful for future on-board engine controls using limited frequency response or heavily filtered pressure transducers. Results of using this knock indicator as a diagnostic tool on a multi-cylinder engine with a spark plug-mounted transducer are presented.