基于动力学和扩散分段控制的Mg/H_2O反应模型及数值分析  

Numerical Analysis of Reaction Characteristics of Mg with Vapor Based on Diffusional and Chemical Dynamic Control

作　　者：周星[1] 张炜[1] 杨栋[1] 鲍桐[1] 姚汝亮[1] 

机构地区：[1]国防科技大学航天与材料工程学院,湖南长沙410073

出　　处：《国防科技大学学报》2011年第1期35-38,共4页Journal of National University of Defense Technology

基　　金：国家安全重大基础研究资助项目(613500103)

摘　　要：为了数值研究宽广温度范围内Mg/H2O的反应特性,分别建立了考虑部分MgO在液滴表面凝聚的Mg/H2O扩散燃烧模型和基于Arrhenius公式的Mg/H2O反应动力学模型。数值研究了Mg/H2O反应速率在扩散控制和化学动力学控制下随反应条件变化的规律。研究结果表明,Mg液滴扩散燃烧时间计算结果与文献值相符;提高温度和水蒸汽浓度有利于扩散燃烧速率增大,增大压强使燃速降低。不同温度段Mg/H2O反应速率控制因素不同,低温段反应速率受动力学控制,高温段反应速率受扩散控制。In order to numerically study the reaction characteristics of magnesium and vapor in broad temperature range,the reaction model based on diffusional and chemical dynamic control respectively was established.The diffusional control model considered the partial condensation of gaseous MgO on the surface of magnesium droplet.The chemical dynamic model of Mg/H2O reaction was based on the Arrhenius equation.The reaction rate of Mg/H2O at different conditions was studied numerically.The results show that the calculated results are consistent with the experimental results.The reaction rate is great at high temperature and concentration of vapor,but low at high pressure.The reaction rate of magnesium and vapor is controlled by different factors at different temperature region.The reaction rate is controlled by chemical dynamic below the critical transition temperature,but by diffusional dynamic above the critical transition temperature.

关 键 词：水冲压发动机 镁-水反应 扩散控制 化学动力学控制 

分 类 号：V512[航空宇航科学与技术—航空宇航推进理论与工程]