基于反应欧拉方程投影算法的广域尺度气体爆炸数值模拟研究  

Numerical study of large-scale gas explosions based on projection method for reactive Euler equation

作　　者：李立彬 喻鑫龙 刘青泉[1] 王晓亮 LI LiBin;YU XinLong;LIU QingQuan;WANG XiaoLiang(School of Aerospace Engineering,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学宇航学院,北京100081

出　　处：《中国科学：技术科学》2023年第4期601-614,共14页Scientia Sinica(Technologica)

基　　金：国家自然科学基金(批准号:12032005,12172057)资助项目。

摘　　要：近年来广域尺度可燃气体爆炸事故愈发严重,亟需发展有效的数值方法模拟爆炸波的传播发展及其对结构物的作用,预测和评估爆炸造成的危害.本文采用含极端刚性源项的反应欧拉方程描述广域尺度气体爆炸过程,基于算子分裂法,通过高分辨率格式捕捉激波,采用投影法处理化学反应刚性源项,解决了化学反应和流体动力学时空尺度不匹配的问题.通过若干一维爆轰波算例验证了本文数值方法能够在网格尺度欠解析的情况下准确捕捉爆轰波的传播过程,且几乎不受空间重构格式的影响,具有较好的鲁棒性.进一步将一维数值模型推广至二维含复杂结构物气体爆炸问题,几组二维算例表明本文数值模型能够在较粗的网格条件准确捕捉弯曲爆轰波的传播及其散射行为.最后计算了一个广域尺度含复杂结构物的爆炸波算例,表明本文的数值方法具备在空间网格欠解析的情况下模拟真实广域尺度气体爆炸问题的能力,有望为城市爆炸安全评估提供压力、温度等数据.Wide-area scale gas blast accident has become more severe recently;therefore,it is urgent to develop effective numerical methods to simulate the propagation of the explosion wave and the structural effect to forecast and estimate the damage.Herein,the reactive Euler equation with an extremely stiff source term is used to describe a wide-area scale gas blast.A numerical method based on the operator-splitting technique,using a high-resolution scheme for shock capturing and a novel projection method for the stiff source term,is proposed to handle the multiscale problem in reactive flows with extreme chemical reactions.Some one-dimensional(1D)detonation examples are successfully simulated to demonstrate that the proposed numerical method can capture the propagation process of the detonation wave in an underresolved mesh.The examination of the reconstruction methods implies that the proposed method is robust and unaffected by the spatial reconstruction schemes.Furthermore,the numerical model is extended to a 2D gas blast problem with complex structures.Several 2D detonation examples are simulated to show that the proposed numerical method can accurately capture the propagation and scatter behavior of detonation in high dimensions with a coarse mesh.Finally,a wide-area scale blast wave example that contains complex structures is simulated to provide the evolution of the gas blast wave and its interaction with structures in a coarse mesh.The numerical method proposed herein is a promising tool that can simulate the gas blast on a wide-area scale to provide pressure and temperature for city safety assessment under gas explosion accidents.

关 键 词：爆炸 刚性 化学反应 投影法 广域 

分 类 号：X932[环境科学与工程—安全科学]