论文部分内容阅读
以圆管内壁催化剂薄层内发生甲烷水蒸气重整反应为研究对象,对层流条件下反应及换热进行了数值模拟,分析了催化剂活性、薄层厚度、入口气体流量、入口压力、入口温度以及反应物组分比对反应和换热的影响.结果表明:催化剂薄层内的吸热反应可以有效地增强换热,降低壁面温度;提高催化剂活性和增加薄层厚度,可以增加化学反应吸热量,降低壁面温度,但是当薄层厚度达到一定值时,再增加薄层厚度效果很小;入口流量越大,反应转化率越小,化学反应吸热量占总吸热量的比例越小;入口压力越大,反应吸热量越小,壁面温度越高;提高入口温度使得近入口处壁面温度升高,但是对下游壁面温度的影响很小;存在最佳的反应物组分比,从而获得较低的壁面温度和较高的出口氢气含量.
Taking the steam reforming reaction of methane in the catalyst thin layer on the inner wall of the tube as the research object, the numerical simulation of the reaction and heat transfer under the laminar flow condition was carried out. The effects of the catalyst activity, the thickness of the thin layer, the inlet gas flow rate, the inlet pressure, Temperature and reactant composition ratio on the reaction and heat transfer.The results show that the endothermic reaction in the catalyst layer can effectively enhance the heat transfer and reduce the wall temperature; improve the catalyst activity and increase the thickness of the thin layer can increase the chemical reaction Heat absorption, reduce the wall temperature, but when the thickness reaches a certain thickness, then the effect of increasing the thickness of the thin layer is small; the larger the inlet flow rate, the smaller the conversion rate of the reaction, the proportion of chemical reaction endothermic heat total heat The smaller the inlet pressure is, the smaller the amount of heat absorbed is and the higher the wall temperature is. The higher the inlet temperature, the higher the wall temperature near the inlet, but the smaller the temperature of the downstream wall. , Resulting in lower wall temperatures and higher outlet hydrogen content.