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This paper summarizes the results of a survey and analysis of cold starting data for spark ignition engines utilizing high methanol blends. All available published information, as well as additional data supplied by contributing agencies was considered. The report includes graphical comparisons of test results and a detailed discussion of the various factors which influence cold starting. Recommendations are made for further work needed to improve cold starting.

A methanol fuelled single cylinder research engine was tested under simulated cold start conditions of 0°C. The engine instrumentation provided dynamic measurements of pressures and temperatures in the cylinder, inlet port, and exhaust port. Initially, tests were conducted to gain a better understanding of the metabolism of methanol cold starting under limit conditions. Following these tests the exhaust charged cycle (ECC), a form of prompt exhaust gas recirculation, was employed as a means of improving in-cylinder mixture formation during starting. Tests using a special camshaft to obtain prompt EGR showed that successful starts using neat methanol could be achieved if ignition occurred during cranking. Thus, unlike the standard engine configuration, the ignition and starting limits with the prompt EGR system were essentially the same.

This paper summarizes the results of a survey and analysis of cold starting data for spark ignition engines utilizing neat methanol. All available published information, as well as additional data supplied by contributing agencies was considered. The report includes graphical comparisons of test results and a detailed discussion of the various factors which influence cold starting. Recommendations are made for further work needed to improve cold starting.

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.

Computational procedures are described for combining a simple multicomponent fuel volatility model with flammability data to facilitate the analyses of a wide variety of practical situations involving methanol/ gasoline blends. These include fire hazards, fuel droplet or film evaporation, ignition, combustion and engine cold starting. In addition to outlining the computational procedures, several examples are given to illustrate possible applications. In particular, gasoline and M85 are compared as to their respective flashpoints, flammability of fuel tank headspace vapours, and fuel droplet evaporation under cold ambient conditions.