农用增压柴油发动机排气歧管优化

Optimization of exhaust manifold for farm-oriented supercharged diesel engine

为了提高某款农用增压柴油发动机的低速性能,对发动机的排气歧管进行优化。运用AVL BOOST软件建立发动机的数值仿真模型,并进行模型的标定。改变排气歧管布置方式,研究排气歧管布置方式对发动机低速性能的影响。在此基础上,为进一步提高发动机扭矩、降低油耗,在发动机最大扭矩工况下,对比排气歧管不同长度和直径时发动机的性能,确定排气歧管的最佳尺寸。结果表明,经过优化后的发动机低速工况动力性和经济性均有不同程度的改善。

This is in order to improve the low-speed performance of the farm-orlented turbocharged diesel engine. The numerical simulation model of the engine was established by using AVL BOOST software, and the calibration was conducted. Through changing the exhaust manifold layout, its influence on engine low-speed performance was researched. On this basis, in order to further increase the engine torque and reduce the fuel consumption, the optimum size of the exhaust manifold was determined by comparing the engine performance with different length and diameter exhaust manifold under the maximum torque of the engine operating conditions. It shows that after optimization the power and economy of the engine at low-speed range were improved.