基于ReaxFF MD方法的煤焦增压富氧燃烧模拟  

Simulation on Pressurized Oxy-fuel Combustion of Coal Char Based on ReaxFF MD Method

作　　者：洪迪昆 雷鸣 翟晓明 郭欣[2] HONG Dikun;LEI Ming;ZHAI Xiaoming;GUO Xin(Department of Power Engineering,North China Electric Power University,Baoding 071003,Hebei Province,China;State Key Laboratory of Coal Combustion,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]华北电力大学动力工程系,河北保定071003 [2]华中科技大学煤燃烧国家重点实验室,武汉430074

出　　处：《动力工程学报》2022年第4期302-308,共7页Journal of Chinese Society of Power Engineering

基　　金：国家自然科学基金资助项目(52006081);中央高校基本科研业务费专项资金资助项目(2021MS080)。

摘　　要：基于实验表征结果构建了准东五彩湾煤焦的分子结构模型,采用基于反应力场的分子动力学(ReaxFF MD)方法研究了压力对准东五彩湾煤焦富氧燃烧的影响,并通过分析煤焦结构的演变从微观分子层面上揭示了压力对煤焦氧化反应和气化反应的影响机制。结果表明:煤焦的整体碳转化率随着压力的升高而增加;增压提高了氧化反应对煤焦转化的净贡献,却降低了气化反应对煤焦转化的净贡献;增压降低了煤焦氧化反应的活化能,但对煤焦气化反应活化能的影响并不明显。The molecular structure model of Wucaiwan coal char was constructed based on experimental characterization.The effect of pressure on the oxy-fuel combustion of Wucaiwan coal char was studied using reactive molecular dynamics(ReaxFF MD)simulation.The mechanism of the effect of pressure on char-O_(2)oxidation reactions and char-CO_(2)gasification reactions was revealed by analyzing the evolution of char microstructure.Results show that with the increase of pressure,the overall carbon conversion of char increases,and the net contribution of char-O_(2)oxidation to char conversion increases,while the net contribution of char-CO_(2)gasification to char conversion decreases.Increasing pressure can reduce the activation energy of char-O_(2)oxidation reactions,but has a little effect on the activation energy of char-CO_(2)gasification reactions.

关 键 词：富氧燃烧 煤焦 压力 气化反应 分子动力学 

分 类 号：TK227.1[动力工程及工程热物理—动力机械及工程]