某8缸直列船用发动机水套排气管结构设计

Design of water jacket exhaust pipe layout of 8-cylinder inline marine engine

为降低船舱温度,为某8缸直列双增压发动机设计脉冲式水套排气管结构方案。利用GT-Power软件搭建发动机3种水套排气管热力学仿真计算模型,对比3种方案的燃油消耗率和泵气损失,确定各方案的最优主直径,通过对比3种方案在最优主直径时燃油消耗率、排气泵气损失、各缸排温均匀性、排气质量流量等性能参数优选水套排气管结构。结果表明:方案1在排气管直径62 mm时油耗、排气泵气损失、排气回流最低、排温均匀性最好,是该机型水套排气管的最优结构。

To reduce cabin temperature,three pulse type exhaust pipe with water jacket structures are designed for an 8-cylinder inline dual turbocharged engine.The thermodynamic simulation calculation model for the engine water jacket exhaust pipe is established using GT-Power simulation software.The optimal main diameter of each scheme is determined by comparing the fuel consumption rate and pump loss of three schemes.Optimize the structure of the water jacket exhaust pipe by comparing the performance parameters such as fuel consumption rate,exhaust pump air loss,exhaust temperature uniformity of each cylinder,and exhaust mass flow rate of the three schemes at the optimal main diameter.The results show that option 1 has the lowest fuel consumption,the lowest exhaust pump loss,the best exhaust temperature uniformity,and the lowest exhaust inverse flow when the exhaust pipe diameter is 62 mm,making it the optimal water jacket exhaust pipe structure for this model.