• 高速空气动力学 •

### 各向同性湍流通过正激波的演化特征研究1)

1. 西北工业大学航空学院,西安 710072
• 收稿日期:2018-04-18 修回日期:2018-04-18 出版日期:2018-11-18 发布日期:2018-12-04
• 作者简介:2) 洪正,硕士研究生,主要研究方向：激波湍流相互干扰. E-mail: hongzheng@mail.nwpu.edu.cn
• 基金资助:
1) 国家自然科学基金资助项目(11732013).

### STUDY ON EVOLUTION CHARACTERISTICS OF ISOTROPIC TURBULENCE PASSING THROUGH A NORMAL SHOCK WAVE1)

Hong Zheng2), Ye Zhengyin

1. School of Aeronautics, Northwestern Polytechnical University, Xi'an 710072, China
• Received:2018-04-18 Revised:2018-04-18 Online:2018-11-18 Published:2018-12-04

Abstract: Shock-turbulence interaction is a kind of important fundamental problem in aerodynamics. Based on solver Helios which applies cell-centered finite difference method (CCFDM), using fifth-order weighted compact nonlinear scheme (WCNS), we conducted direct numerical simulation (DNS) of the situation where isotropic turbulence passes through a normal shock wave. Turbulence statistics are calculated for analysis. We found after shock, density is a little lower than its non-turbulent value, so do temperature and pressure, on the contrary, longitudinal velocity is a little higher than its non-turbulent value. The commonality is that they all show an overshoot immediately behind the shock, after that they gradually approach towards their non-turbulent values along with downstream distance. Longitudinal Reynolds stress suffers a sudden decrease and increases rapidly followed by decaying. This evolution characteristics is captured in linear interaction analysis (LIA) and a transfer of energy from acoustical to vertical modes behind the shock is thought to be accounted for it according to this analysis. Different from longitudinal Reynolds stress, Transverse Reynolds stress suffers a sudden increase then decay monotonically. Anisotropy of Reynolds stress is apparent after shock, and it gradually increases as downstream distance increases. Turbulent kinetic energy suddenly increases and then evolves non-monotonically. Taylor microscale and Kolmogorov scales apparently decrease after shock, indicating the decrease of turbulent length scales, which leads to a requirement of higher resolution of mesh in this zone to solve the flow field. After shock, the root-mean-squares of density, temperature and pressure fluctuations are enhanced, and intensities of density and pressure decrease while intensity of temperature increases.

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