可压缩多项流问题的数值研究及应用

发布时间:2018-08-29 19:11
【摘要】:在可压缩多相流的数值模拟研究中,带自由界面的Cut-Cell方法已经由Chang等人(2013)[1]所发展,我们使用基于此方法所发展起来的MuSiC~+程序,数值研究了包含气体-气体,气体-液体以及气体-固体介质的Richtmyer-Meshkov(RM)界面不稳定,验证了气-液介质小扰动振幅下的界面增长率在前期符合Yang等人(1994)[2]提出的线性化模型,后期符合ZhangSohn(1996,1997)[3,4]提出的非线性模型:模拟了有着广泛应用前景的微射流问题,通过修改Peters等人2013[5]的模型,得到了一个适用于由激波诱导的微射流演化过程中最大速度与初始接触角,激波强度的半经验关系式;通过数值拟合获得了一个适用于高Mach数情形的射流最大速度的模型关系式。考虑到在MuSiC~+程序的实现中,Chang等人通过Level Set函数值来演化物质界面,并引入小网格单元的切分和融合,以此来刻画自由界面,在界面演化的过程中通过对界面速度的传播及插值来完成对界面附近网格点的速度的赋值,这样的处理在界面发生严重变形尤其是在有界面拓扑结构变化发生的一些问题时,对一个网格被界面多次切分的现象还需考虑。通过继承MuSiC~+程序中的网格切分的思想,参考Hu等人(2006)提出的一种守恒界面方法[6]的一些界面处理过程,以及引入Ghost fluid的方法(Fedkiw 1999,2001,2002[7-9];Liu 2003,2005[10,11]),在界面处我们提出 了一种 real-ghost mixing 的切分网格状态的处理方法,这种方法很好的处理了在含有物质界面拓扑结构变化的一些多相流问题的演化模拟。新发展的数值方法(我们称之为一种基于切割网格和ghost fluid的可压缩多相流求解方法,简记为CCGF)通过对一维激波管问题(Air-SF6,Air-Helium,Water-Air)的计算,以及与解析解的比较,能够看出是准确的;通过对大量二维经典问题(Air-SF6以及Air-Helium的Richtmyer-Meshkov的界面不稳定问题,Air-Helium以及Air-R22的激波气泡相互作用问题,水下气泡在强激波作用下的破碎问题,水下爆炸问题,空气中激波撞击液柱及双液柱问题)的模拟研究,以及比较相关实验结果和之前的数值研究结果,能够看出目前的数值方法是可信的。使用MuSiC~+程序与CCGF程序,数值研究了气体-气体介质的RM不稳定性,给出了界面演化的分布图,界面增长率的变化曲线图,分析了引起界面增长率震荡的原因,并和已有的理论结果(Yang等人线性化模型结果,ZhangSohn的非线性模型(ZS),Sadot等人非线性模型(SEA)[12],DimonteRamaprabhu的非线性模型(DR)[13])以及数值结果(Holmes等人[14,15],茅德康等人[16])做比较。通过考虑不同初始扰动振幅下的界面增长,进一步验证在小扰动情形下三个非线性模型与数值结果是一致的;对于大扰动情形,DR模型与数值结果有很好的一致性,ZS模型过低的估计了界面增长,SEA模型则高估界面的扰动增长。为了研究更为复杂的流动问题(多介质液滴的相互碰撞和穿透问题),我们试图同时使用基于MuSiC~+程序的数值方法和基于CCGF的数值方法来解决这类问题,考虑在多界面情况下两种方法共同使用分别处理不同界面的流动,甚至也考虑在两相流的不同演化阶段采用不同的方法来模拟研究,目前我们已经能够实现在两相流问题中两种不同方法的相互转化使用,通过对水下激波作用下气泡破碎问题的模拟,能够看出两种方法的相互转化来模拟一个问题是成功的。两种方法共存模拟多界面问题是未来的工作。
[Abstract]:In the numerical simulation of compressible multiphase flow, the Cut-Cell method with free interface has been developed by Chang et al. (2013)[1]. Using the MuSiC~+ program developed based on this method, the Richtmyer-Meshkov (RM) interfacial instability including gas-gas, gas-liquid and gas-solid media has been numerically studied. The interfacial growth rate under small disturbance amplitude of gas-liquid medium conforms to the linearized model proposed by Yang et al. (1994) [2] in the early stage and to the nonlinear model proposed by Zhang Sohn (1996, 1997) [3, 4] in the later stage. The problem of micro-jet with wide application prospects is simulated. By modifying the model of Peters et al. [5] in 2013, a model suitable for shock induced flow is obtained. A semi-empirical relationship between the maximum velocity and the initial contact angle and the shock intensity in the evolution process of a guided micro-jet is obtained by numerical fitting. Considering the realization of MuSiC~+ program, Chang et al. used Level Set function to evolve the material interface, and introduced a new model to describe the maximum velocity of a guided micro-jet. In the process of interface evolution, the velocity of grid points near the interface is assigned by the propagation and interpolation of the velocity of the interface. In this way, the interface is severely deformed, especially when there are some problems of interface topological structure changes. By inheriting the idea of grid segmentation in MuSiC~+ program, referring to some interface processing procedures of Hu et al. (2006) and introducing Ghost fluid (Fedkiw 1999, 2001, 2002 [7-9]; Liu 2003, 2005 [10, 11]), we propose a new method at the interface. The real-ghost mixing method, which deals well with the evolutionary simulation of some multiphase flow problems involving changes in the topology of the material interface, is presented. Comparing with the analytical solutions, it can be seen that the calculation of the one-dimensional shock tube problem (Air-SF6, Air-Helium, Water-Air) is accurate; through a large number of two-dimensional classical problems (Air-SF6 and Air-Helium's Richtmyer-Meshkov interface instability problem, Air-Helium and Air-R22's shock bubble interaction problem, underwater bubble in strong excitation The present numerical method is believable by comparing the experimental results with the previous numerical results. The RM instability of gas-gas medium is numerically studied by using the MuSiC~+ and CGF codes. In this paper, the distribution of interface evolution and the change curve of interface growth rate are given, and the reasons causing the oscillation of interface growth rate are analyzed. The results are compared with the existing theoretical results (Yang et al. linear model, Zhang Sohn's nonlinear model (ZS), Sadot et al.'s nonlinear model (SEA) [12], Dimonte Ramaprab's nonlinear model (DR) [13]) and numbers. Numerical results (Holmes et al. [14,15], Mao Dekang et al. [16]) are compared. Considering the interface growth under different initial disturbance amplitudes, it is further verified that the three nonlinear models are consistent with the numerical results in the case of small disturbance; for the case of large disturbance, the DR model is in good agreement with the numerical results, and the ZS model underestimates the interface. In order to study more complex flow problems (collision and penetration of droplets in multi-media), we attempt to solve these problems simultaneously by using numerical methods based on MuSiC~+ program and CGF. In dealing with the flow at different interfaces, different methods are even considered to simulate the two-phase flow at different stages of evolution. At present, we have been able to realize the mutual conversion of two different methods in the two-phase flow problem. To simulate a problem is successful. The two method of coexistence and Simulation of multiple interface problems is the future work.
【学位授予单位】:中国科学技术大学
【学位级别】:博士
【学位授予年份】:2016
【分类号】:O359

【参考文献】

相关期刊论文 前10条

1 刘军;冯其京;周海兵;;柱面内爆驱动金属界面不稳定性的数值模拟研究[J];物理学报;2014年15期

2 刘金宏;邹立勇;曹仁义;廖深飞;王彦平;;绕射激波和反射激波作用下N_2/SF_6界面R-M不稳定性实验研究[J];力学学报;2014年03期

3 罗喜胜;王显圣;陈模军;翟志刚;;可控肥皂膜气柱界面与激波相互作用的实验研究(英文)[J];实验流体力学;2014年02期

4 施红辉;肖毅;杜凯;吴宇;;用垂直激波管研究多层流体界面上的Richtmyer-Meshkov不稳定性[J];中国科学技术大学学报;2013年09期

5 刘金宏;谭多望;柏劲松;黄文斌;邹立勇;张旭;;激波管实验研究非均匀流场R-M不稳定性[J];实验力学;2012年02期

6 施红辉;杜凯;王超;章利特;贾会霞;董若凌;;不同密度梯度的多层流体界面上的Richtmyer-Meshkov不稳定性研究[J];实验流体力学;2011年05期

7 M.A.ULLAH;高文斌;茅德康;;Numerical simulations of Richtmyer-Meshkov instabilities using conservative front-tracking method[J];Applied Mathematics and Mechanics(English Edition);2011年01期

8 何长江;周海兵;杭义洪;;爆轰驱动金属铝界面不稳定性的数值分析[J];中国科学(G辑:物理学 力学 天文学);2009年09期

9 ;Numerical investigation of Richtmyer-Meshkov instability driven by cylindrical shocks[J];Acta Mechanica Sinica;2006年01期

10 ;Two-phase Flow Patterns in a Square Mini-channel[J];Journal of Thermal Science;2004年02期



本文编号:2212138

资料下载
论文发表

本文链接:https://www.wllwen.com/shoufeilunwen/jckxbs/2212138.html


Copyright(c)文论论文网All Rights Reserved | 网站地图 |

版权申明:资料由用户c52e8***提供,本站仅收录摘要或目录,作者需要删除请E-mail邮箱bigeng88@qq.com