甲醇裂解器起燃特性的试验研究

摘要

As an alternative fuel,methanol directly applied in liquid form will corrode engine.Using exhaust heat to methanol cracking after burning,can effectively alleviate the problem of cold start behavior of methanol.This paper focuses on the light-off characteristics of methanol reformer and its influencing factors in engine's cold starting.The testing results show that the light-off time significantly increases when engine block and exhaust pipe are at lower temperature.The light-off process can be speeded up by raising engine's load and speed after starting as well as reduce spark advance.Road simulation results indicate that the reformer temperature rising speed would be reduced for heat dissipating caused by air motion intensification.Methanol reforming is affected by the temperature of methanol reformer,and it is necessary to cover the exhaust pipe and the reformer system with heat insulation materials in real application.%甲醇作为发动机替代燃料，以液态形式直接应用会腐蚀发动机。利用排气余热将甲醇裂解后燃烧，可有效缓解纯甲醇发动机冷起动困难的情况。文章通过台架试验，对甲醇裂解器的起燃过程进行了研究，分析了环境温度和发动机起动后负荷加载情况对裂解器起燃时间的影响。结果表明：环境温度的提高、发动机转速和负荷的增加以及点火提前角的推迟会有效缩短甲醇裂解器的起燃时间；模拟道路工况下，随着排气管及裂解器处的气流运动加剧，导致其散热速率加快，裂解器温度上升缓慢，甲醇裂解率受裂解器入口温度的影响较大。