基于ReaxFF场的矿物绝缘油热解分子动力学模拟  

Molecular Dynamics Simulation of Mineral Insulating Oil Pyrolysis Based on Force Field ReaxFF

作　　者：杜林[1] 王五静 张彼德[2] 王誉博 相晨萌[1] 王杰 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]西华大学电气与电子学院,610039 [3]国网四川省电力公司电力科学研究院,成都610072

出　　处：《高电压技术》2018年第2期488-497,共10页High Voltage Engineering

基　　金：四川省科技厅应用基础研究项目(2017JY0204)~~

摘　　要：热故障是影响充油设备安全运行的重要因素,基于Reax FF力场的分子动力学模拟方法建立了含有30个分子的矿物绝缘油仿真模型,深入研究了不同温度下矿物绝缘油的动态热解过程和产气规律。通过Reactive-MD-analysis识别模块对矿物绝缘油热解产物的识别和统计,结合仿真的动态图像分析了矿物油的微观反应过程,得出矿物油热解的主要反应路径以及小分子气体的生成路径。同时重点分析了温度对热解微观过程的影响,结果表明：中温下大分子烃自由基的β–C断裂造成C_2H_4气体的大量产生;高温下C_3H_8、C_2H_6和C_2H_4的继续分解造成C_2H_6和C_2H_4气体的相继减少以及H_2、CH_4和C_2H_2气体的不断增多。通过与热重实验结果的对比,验证了仿真结果的合理性,说明ReaxFF反应动力学模拟为从分子上研究矿物绝缘油的热解提供了一种有效的途径。Thermal faults threaten the safe and stable operation of oil filled equipment. Based on Reax FF, a molecular dynamics simulation method was used to establish the simulation model of mineral insulating oil molecules. And the dynamic pyrolysis process and produce regularity of gaseous molecules in mineral insulating oil were studied under different temperatures. Through dynamic images and analysis for the pyrolysis products of mineral insulating oil under different temperatures and time, the microcosmic reaction process of insulating oil was analyzed. Then, the pyrolysis reaction path and the production path of small molecules were concluded. The dynamic images and analysis were gotten by a reactive-MD-analysis model. Then the focus was fixed on the effect of temperature on the micro process. The results show that, under the medium temperatures, the β-C crack of macromolecular hydrocarbon radicals will cause the emergence of C_2H_4; under high temperatures, the constant crack of C_3H_8, C_2H_6 and C_2H_4 caused the decrease of C_2H_6 and C_2H_4 one after another, as well as the constant increase of H_2, CH_4 and C_2H_2. By comparisons with the TG-DSC test, the rationality of the simulation results was proved. So the Reax FF molecular dynamics simulation can provide an effective way to study the pyrolysis of the mineral insulating oil.

关 键 词：矿物绝缘油 热解 ReaxFF场 温度 分子动力学模拟 Reactive-MD-analysis 

分 类 号：TM215.4[一般工业技术—材料科学与工程]