带有水夹套的防爆柴油机后处理装置流动与传热特性耦合研究  

Study on coupling of flow and heat transfer characteristics of postprocessing device with water jacket of explosion-proof diesel engine

作　　者：白炳仁 倪计民[1] 石秀勇[1] 刘越[1] 李佳琪[1] 金文华[1] 

机构地区：[1]同济大学汽车学院,上海201804

出　　处：《矿山机械》2017年第8期25-32,共8页Mining & Processing Equipment

摘　　要：针对矿用车辆排气系统防爆性能要求高的问题,建立防爆柴油机含水夹套后处理装置流动及传热仿真模型,采用直接耦合法进行数值模拟,并通过试验验证模型准确性。在此基础上对后处理装置的气-水-固耦合传热进行分析,对冷却水流量与温度、水夹套厚度及混合器孔径等影响其流动与传热特性的因素进行深入研究。研究结果表明:水夹套外壳最高温度出现在排气出口处的法兰端面上部,此处超温风险最大;催化器载体表面温度均匀性随冷却水流量升高而降低,随冷却水温度升高而升高;适当增大水夹套厚度既可降低水夹套外壳表面最高温度,又能降低冷却水压降和水泵耗功;混合器虽能提高载体表面温度均匀性,但对水夹套外壳表面最高温度的控制却是不利的,且表面最高温度随着孔径的增大而提高。In order to improve the explosion-proof performance of the exhaust system of the mine-used vehicle, the simulation model of the flow and heat transfer of the post-processing device with water jacket of an explosion-proof diesel engine was established. The direct coupling method was used to conduct the numerical simulation, and the accuracy of the model was verified after test. On the basis of the simulation model, the gaswater-solid coupling heat transfer of the post-processing device was analyzed, and the factors affecting the flow and heat transfer characteristics such as the flow and the temperature of the cooling water, the thickness of the water jacket and the hole diameter of the mixer were studied. The results indicated that the highest temperature of the water jacket shell appeared at the top of the flange at the exhaust outlet, where it was the most prone to overheat; the surface temperature uniformity of the catalyst carrier decreased with the increase in the flow of the cooling water, and increased with the increase in the temperature of the cooling water. Suitable increase in the thickness of the water jacket not only reduced the maximum temperature on the surface of the water jacket shell, but reduced the pressure drop of the cooling water and the power consumption of water pump; although the addition of the mixer improved the temperature uniformity on the surface of the carrier, it was unfavorable for the control of the maximum temperature on the surface of the water jacket shell, and the maximum surface temperature increased with the increase in hole diameter.

关 键 词：防爆柴油机 后处理装置 CFD 耦合传热 

分 类 号：TD684[矿业工程—矿山机电]