宁德忠，官维，杨葵，王鹏，盛利，高强
广西玉柴机器股份有限公司，广西玉林537005
摘要：为研究燃烧室结构对甲醇发动机缸内流动的影响，通过三维仿真计算和发动机台架测试，对比分析原缩口活塞（原活塞）和优化后的浅盆活塞（优化活塞）对甲醇发动机性能的影响。研究结果表明：台架试验结果与缸内湍动能计算分析结果吻合较好，相比原活塞，优化活塞的缸内滚流尺度明显增大，缸内滚流得到了充分的发展，有利于形成混合气湍流，湍动能增加约30%；优化活塞的缸内混合气混合更均匀，火花塞附近的稀混合气较少，有助于加快火焰的初期发展，优化活塞的燃油经济性更好。该研究对甲醇发动机开发有一定的工程指导意义。
关键词：甲醇发动机；活塞结构优化；湍动能；滚流；涡流；燃油经济性
Abstract：In order to study the effect of the combustion chamber structure on the incylinder gas flow in a methanol engine, the effects of the original necked piston and the optimized shallow basin piston on the performance of methanol engines are compared and analyzed by means of 3D simulation calculation and engine bench test. The results show that the bench test results are in good agreement with the calculation and analysis results of turbulent kinetic energy in the cylinder. The tumble flow scale of optimized piston is significantly larger than that of the original piston, and the tumble flow in the cylinder can be fully developed. This could help the formation of mixture and the increase of turbulent kinetic energy. The turbulent kinetic energy in the combustion chamber with optimized piston is nearly 30% higher than that of the original piston. Additionally, the optimized piston has a more uniform mixture and less dilute mixture near the spark plug. These all speed up the initial flame development. The optimized piston has a better fuel economy compared to the original piston. The research has certain engineering guiding significance for the development of methanol engine.
Keywords:methanol engine; piston optimization; turbulent kinetic energy; tumble; swirl; fuel economy
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