关键词: 爆轰流体力学模型/
不确定度量化/
敏感度分析/
模型确认
English Abstract
Sensitivity analysis and validation of detonation computational fluid dynamics model
Liang Xiao1,2,Wang Rui-Li1
1.Institute of Applied Physics and Computational Mathematics, Beijing 100094, China;
2.College of Mathematics, Shandong University of Science and Technology, Qingdao 266590, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 11372051, 91630312, 11475029), the Fund of the China Academy of Engineering Physics (Grant No. 2015B0202045), the Natural Science Foundation of Shandong, China (Grant No. ZR2015AQ001), and the Defense Industrial Technology Development Program, China (Grant No. C1520110002).Received Date:14 January 2017
Accepted Date:13 March 2017
Published Online:05 June 2017
Abstract:Verification, validation and uncertainty quantification (V&V&UQ) is a method of assessing the credibility of physical model and quantifying the confidence level of numerical simulation result in complex engineering. Verification is used to answer the question whether the physical model is well solved or the program is implemented correctly, and it will give the ranges of error and uncertainty. Validation is used to answer the question whether the physical model reflects the real world or the confidence level of the physical model. This article deals with the detonation computational fluid dynamics model, and analyses the uncertainty factor in modeling, then presents the key factor which affects the accuracy of the simulation result. Due to the complexity of the explosive detonation phenomenon, there are a huge number of uncertainty factors in the detonation modeling. The sensitivity analyses of these uncertainty factors are utilized to distinguish the main factors which influence the output of the system. Then uncertainty quantification is conducted in these uncertain factors. After comparing the simulation result with the experiment data, the adaptation of the model is validated. This procedure is applied to the cylindrical test with TNT explosive. From the result, we can see that the parameters in the JWL EOS are calibrated and the accuracy of the model is validated. By the way, through conducting the uncertainty quantification of this system, we obtain that the expectation and standard deviation of detonation pressure for TNT are 1.6 and 2.2 GPa respectively. Detonation velocity and position of the cylindrical wall accord well with the experiment data. That means that the model is suited in this case. This technique is also extended to the detonation diffraction phenomenon. We can conclude that simulation result is greatly affected by the scale of the cell. From these examples, we can infer that this method also has a wide application scope.
Keywords: detonation computational fluid dynamics model/
uncertainty quantification/
sensitivity analysis/
model validation
