Direct numerical simulation methods of hypersonic flat-plate boundary layer in thermally perfect gas  

作　　者：JIA WenLi CAO Wei 

机构地区：[1]Department of Mechanics,Tianjin University [2]Liu-Hui Center of Applied Mathematics,Nankai University and Tianjin University

出　　处：《Science China(Physics,Mechanics & Astronomy)》2014年第2期336-344,共9页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Nature Science Foundation of China(Grant Nos.11172203 and 91216111);the National Basic Research Program of China(Grant No.2009CB724103)

摘　　要：High-temperature effects alter the physical and transport properties of air such as vibrational excitation in a thermally perfect gas,and this factor should be considered in order to compute the flow field correctly.Herein,for the thermally perfect gas,a simple method of direct numerical simulation on flat-plat boundary layer is put forward,using the equivalent specific heat ratio instead of constant specific heat ratio in the N-S equations and flux splitting form of a calorically perfect gas.The results calculated by the new method are consistent with that by solving the N-S equations of a thermally perfect gas directly.The mean flow has the similarity,and consistent to the corresponding Blasius solution,which confirms that satisfactory results can be obtained basing on the Blasius solution as the mean flow directly in stability analysis.The amplitude growth curve of small disturbance is introduced at the inlet by using direct numerical simulation,which is consistent with that obtained by linear stability theory.It verified that the equation established and the simulation method is correct.High-temperature effects alter the physical and transport properties of air such as vibrational excitation in a thermally perfect gas, and this factor should be considered in order to compute the flow field correctly. Herein, for the thermally perfect gas, a simple method of direct numerical simulation on flat-plat boundary layer is put forward, using the equivalent specific heat ratio instead of constant specific heat ratio in the N-S equations and flux splitting form of a calorically perfect gas. The results cal- culated by the new method are consistent with that by solving the N-S equations of a thermally perfect gas directly. The mean flow has the similarity, and consistent to the corresponding Blasius solution, which confirms that satisfactory results can be obtained basing on the Blasius solution as the mean flow directly in stability analysis. The amplitude growth curve of small disturbance is introduced at the inlet by using direct numerical simulation, which is consistent with that obtained by linear sta- bility theory. It verified that the equation established and the simulation method is correct.

关 键 词：hypersonic fiat-plate boundary layer direct numerical simulation variable specific heat equivalent specific heat ratio 

分 类 号：O354.3[理学—流体力学]