论文部分内容阅读
为深入理解主动冷却过程中碳氢燃料的超临界吸热裂解特性,采用RP-3航空煤油的四组分替代模型、包含18种组分和24步反应的改进Kumar-Kunzru裂解反应动力学模型,对压力为5MPa时管道内RP-3的吸热裂解反应过程进行了数值模拟,研究了裂解反应对燃料物性和传热特性的影响,以及裂解率较高时二次反应对RP-3裂解的影响。结果表明:温度达到890K时,RP-3的裂解率超过20%,其中芳烃占裂解产物的12.1%;RP-3裂解后燃料物性显著变化,管道出口壁温和燃料温度分别降低了130K和129K,努塞尔数提高了16.5%,传热效率显著提高;裂解率较高时二次反应对RP-3裂解的影响较大,相比不考虑二次反应的状态,带二次反应时RP-3裂解率减小了29.1%,管道出口壁温和燃料温度分别降低了34K和22K。
In order to further understand the supercritical endothermic pyrolysis of hydrocarbon fuel during active cooling, a four-component alternative model of RP-3 aviation kerosene was used, which included 18 components and improved Kumar-Kunzru kinetic model , The process of endothermic pyrolysis of RP-3 in the pipeline under pressure of 5MPa was numerically simulated. The effect of pyrolysis reaction on the physical and thermal properties of the fuel and the effect of secondary reaction on the pyrolysis of RP-3 Impact. The results showed that the pyrolysis rate of RP-3 was over 20% at 890K, of which the aromatics accounted for 12.1% of the pyrolysis products. The physical properties of the fuel after RP-3 cracking were significantly changed. The wall temperature and fuel temperature at the outlet of the pipeline were reduced by 130K and 129K, Nusselt number increased by 16.5%, heat transfer efficiency increased significantly; higher cracking rate of the second reaction on the RP-3 cleavage greater than the second reaction does not consider the status of secondary reaction with RP- 3 cracking rate decreased 29.1%, the outlet pipe wall temperature and fuel temperature decreased 34K and 22K respectively.