Mg在CO2/Ar混合气体中的双反应区燃烧模型研究

Combustion model of Mg in CO2/Ar mixture based on double reaction zone

关键词:  金属燃料  Mg/CO₂燃烧模型  火焰层半径  火焰层温度  燃烧时间

Key words:  Metal fuel  Mg/CO₂ combustion model  Flame layer radius  Flame layer temperature  Burning time

摘要:

Mg粉/CO₂是实现火星探测原位资源利用的理想推进剂。针对Mg颗粒在含CO₂混合大气中燃烧，基于火焰层假设，建立了Mg在CO₂/Ar混合气体中的双反应区燃烧模型，分析了Mg在CO₂/Ar燃烧过程中各组分质量分数、各组分流量、颗粒和火焰层的温度分布，研究了环境压强、CO₂质量分数、环境温度和颗粒粒径对燃烧特性的影响。结果表明：环境压强增大，颗粒温度增大、火焰层温度变化不大。在环境压强低于20 kPa时，火焰层半径随环境压强升高快速增大，颗粒燃烧时间随环境压强升高快速变短，随后都基本保持不变；CO₂质量分数增大，颗粒温度与火焰层温度升高、火焰层半径减小、颗粒燃烧时间缩短；环境温度增大，颗粒温度变化不大、火焰层温度升高、火焰层半径减小、颗粒燃烧时间延长；颗粒粒径增大，颗粒温度与火焰层半径变化不大、火焰层温度降低、颗粒燃烧时间延长。

Abstract:

Mg powder/CO₂ is an ideal propellant for in-situ resource utilization of the power plant for Mars exploration. For the combustion of Mg particles in CO₂ mixed atmosphere， a two-reaction zone combustion model for Mg in a CO₂/Ar mixture was developed based on the flame layer hypothesis， and the mass fraction and flow rate of each component， the particles and the flame layer temperature during the combustion of Mg in CO₂/Ar were analyzed， and the effects of ambient pressure， mass fraction of CO₂， ambient temperature and particle size on the combustion characteristics were investigated. The results show that the ambient pressure increases， the particle temperature increases， and the temperature of the flame layer changes little. When the ambient pressure is lower than 20 kPa， the radius of the flame layer increases rapidly with the increase of the ambient pressure， and the particle combustion time decreases rapidly with the increase of the ambient pressure， and then remains almost unchanged. With the increase of oxidant concentration， particle temperature and flame layer temperature increase， flame layer radius and particle combustion time decrease. With the increase of ambient temperature， the particle temperature changes little， the flame layer temperature increases， the flame layer radius decreases， and the particle combustion time increases. With the increase of particle size， the particle temperature and flame layer radius change little， the flame layer temperature decreases， and the particle combustion time increases.