柱形凹坑燃烧室内燃机缸内湍流流动的计算

内燃机缸内流动是具有强压缩性、强旋转和各向异性的复杂的三维湍流流动,对缸内湍流运动的正确描述和模拟,可正确地模拟和分析内燃机的燃烧和排放。应用经修正的RNGk-ε湍流模型对内燃机缸内湍流流动进行数值计算。计算不同结构的柱型凹坑燃烧室缸内流动,特别是对偏心圆柱凹坑燃烧室缸内流动的计算,给出了计算得到的平均湍能的变化及速度变化情况,结果表明,内燃机燃烧室构型对缸内湍流特性有很大的影响,适当改变缸内结构能有效改善缸内流动。

Calculation of Turbulent Flow in Combustion Chamber of Cylindrical Pit in Internal-Combustion Engine

Gas flow in reciprocating internal combustion engine cylinders is complicated, three- dimensional and turbulent, which has a characteristic of high compression, strong rotation and anisotropy. To describe and simulate the turbulent flow in cylinder can accurately simulate and analyze the combustion and exhaustion of internal combustion engine. The modified RNG k - e turbulence model was applied to calculate turbulent flow of internal combustion engine. Turbulent flow in combustion chamber of the different structures' cylindrical pit was calculated, especially in the eccentric column pit's combustion chamber. The changes of average energy and speed of the turbulent flow were given. The result indicates that the cylindrical pit's shape and position have the tremendous influence on the characters of turbulent flow in the cylinder, so reasonable changes in the cylinder's structure can effectively improve the gas flow.