@article{TAN2026, 
author = {Xiaotong TAN and Heyong XU},
title = {Numerical investigation of flow features and aero-optical effects of turrets with different bottom cylinder heights in a transonic flow},
year = {2026},
journal = {Chinese Journal of Aeronautics},
volume = {39},
number = {2},
keywords = {Aero-optical effect, Bottom cylinder height, Dynamic mode decomposition, Flow features, Proper orthogonal decomposition},
url = {https://www.sciopen.com/article/10.1016/j.cja.2025.103717},
doi = {10.1016/j.cja.2025.103717},
abstract = {Improved delay detached eddy simulation is performed to explore the flow features and aero-optical effects of turrets with different bottom cylinder height at a freestream Mach number Ma = 0.7. Analysis of both the time-averaged and instantaneous flow features demonstrate that the shock motion causes the oscillation of separated shear layer. In flow analysis, two unsteady shock-wake-correlated modes are discerned: the asymmetric shifting mode and the symmetric breathing mode. With the increase of cylinder height, the relative energy of shock gradually increases, which goes from 26% to 59%. The proper orthogonal decomposition analysis yields the single frequency peak for the two dominant modes. The frequency peaks of shifting mode are generally at StD < 0.23, while the frequency peaks of breathing mode are generally at StD > 0.26. The dynamic mode decomposition analysis gives range of frequency peak. The frequency peaks of shifting mode are in the range of StD = 0.11–0.23, and the frequency peaks of breathing mode are in range of StD = 0.26–0.41. Optical distortion analysis indicates that the distortion calculated in five cases is linked to the breathing mode. When the beam passes through the turbulent wake, it exhibits the high-frequency and high-amplitude characteristics.}
}