This work explores the methanol compression ignition combustion assisted with glow plug in a light-duty diesel engine. An extensive computational study was conducted to optimize the position of the glow plug. The effects of spray umbrella angle, the relative angle between the glow plug and jet, and the injection strategy on the engine performance were evaluated. Of these parameters, the relative angle between the glow plug and jet was found to be the dominant factor affecting the ignition and flame propagation processes. At each position of the glow plug, the optimum relative angle differed due to the complex flow and air-fuel mixing within the combustion chamber. The removal of the swirling flow resulted in the earlier ignition and combustion phasing. However, the engine`s thermal efficiency was reduced due to the increased combustion loss. In addition, compared to the single injection strategy, the split injection strategy was more effective in promoting the ignition process. The narrower spray included angle yielded better fuel economy because less fuel was trapped within the squish region, leading to faster flame propagation and more advanced combustion phasing. However, even after optimizations, the engine still suffered from a high incomplete combustion loss. To mitigate this issue, the effect of dual glow plugs was examined. The engine performance was significantly improved due to the generated multi-ignition pockets.
Session:
Poster
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