船用气道喷射式甲醇发动机喷射参数对整机性能的影响

许晓颖^1，2，游凯^1，2，颜鲁^1，2，迟昊^1，2，沈富超^1，2，方桦^1，2，陈宁^1，2

1.潍柴动力股份有限公司，山东 潍坊  261061；2.内燃机与动力系统国家重点实验室，山东 潍坊  261061

摘要：为研究由某船用天然气发动机改装的船用甲醇发动机的整机性能，采用Converge软件进行三维流体仿真，分析喷孔参数、甲醇轨压对甲醇雾化的影响，采用GT-Power软件进行一维仿真，分析配气相位对发动机进、排气性能的影响，并选取最佳仿真选型设计，结合台架试验进行最佳喷射结束角选型及整机性能验证。结果表明：喷孔数为16，喷孔直径为0.27 mm，轨压为600 kPa，进气门开启、进气门关闭、排气门开启、排气门关闭时曲轴转角（上止点后）分别为344°、570°、104°、409°，为最佳喷射系统仿真选型设计；最佳选型设计下进气门最大升程为12.0 mm，排气门最大升程为13.5 mm；喷射结束时曲轴转角为330°时，该发动机不同用途下标定工况对应的最小甲醇消耗率台架试验结果分别为433.2、426.5 g/（kW·h），满足此机型产品开发中最小甲醇消耗率小于440 g/（kW·h）的目标要求。

关键词：甲醇发动机；喷射结束；甲醇消耗率；轨压；配气相位

The influence of injection parameters on the overall performance of the marine inlet jet methanol engine

XU Xiaoying^1,2, YOU Kai^1,2, YAN Lu^1,2, CHI Hao^1,2, SHEN Fuchao^1,2, FANG Hua^1,2, CHEN Ning^1,2

1. Weichai Power Co., Ltd., Weifang 261061, China;

2. State Key Laboratory of Engine and Powertrain System, Weifang 261061, China

Abstract: In order to study the overall performance of a marine methanol engine modified from a natural gas engine, Converge software is used for 3D fluid simulation to analyze the effects of nozzle parameters and methanol rail pressure on methanol atomization. GT-Power is used for one-dimensional simulation analysis to investigate the influence of valve timing on engine intake and exhaust performance, and the optimal simulation parameter combinations is selected. Combined with bench tests, the optimal injection end timing selection and overall performance verification are carried out. The results show that the best parameters combinations are 16 injection holes, 0.27 mm diameter of the injection holes, 600 kPa rail pressure, 344° intake valve open, 570° intake valve closed, 104° exhaust valve open, and 409° exhaust valve closed, 12.0 mm maximum lift of the intake valve, 13.5 mm maximum lift of the exhaust valve. When the crankshaft angle is 330° at the end of injection, the minimum methanol consumption rate corresponding to the calibration conditions of the engine under two different uses is 433.2 g/(kW·h) and 426.5 g/(kW·h), which meets the target requirement of a minimum methanol consumption rate of less than 440 g/(kW·h) in the product development.

Keywords: methanol engine; injection end; methanol consumption rate; rail pressure; valve timing