Grupo de Mecánica de Fluidos, Universidad Carlos III de Madrid, Leganés, 28911, Spain.
College of Energy Engineering, Zhejiang University, 310027 Hangzhou, People's Republic of China.
Phys Rev E. 2017 Nov;96(5-1):053104. doi: 10.1103/PhysRevE.96.053104. Epub 2017 Nov 9.
Linear interaction analysis (LIA) is employed to investigate the interaction of reactive and nonreactive shock waves with isotropic vortical turbulence. The analysis is carried out, through Laplace-transform technique, accounting for long-time effects of vortical disturbances on the burnt-gas flow in the fast-reaction limit, where the reaction-region thickness is significantly small in comparison with the most representative turbulent length scales. Results provided by the opposite slow-reaction limit are also recollected. The reactive case is here restricted to situations where the overdriven detonation front does not exhibit self-induced oscillations nor inherent instabilities. The interaction of the planar detonation with a monochromatic pattern of perturbations is addressed first, and then a Fourier superposition for three-dimensional isotropic turbulent fields is employed to provide integral formulas for the amplification of the kinetic energy, enstrophy, and anisotropy downstream. Transitory evolution is also provided for single-frequency disturbances. In addition, further effects associated to the reaction rate, which have not been included in LIA, are studied through direct numerical simulations. The numerical computations, based on WENO-BO4-type scheme, provide spatial profiles of the turbulent structures downstream for four different conditions that include nonreacting shock waves, unstable reacting shock (sufficiently high activation energy), and stable reacting shocks for different detonation thicknesses. Effects of the propagation Mach number, chemical heat release, and burn rate are analyzed.
线性相互作用分析(LIA)用于研究反应性和非反应性冲击波与各向同性涡旋湍流的相互作用。通过拉普拉斯变换技术进行分析,考虑了在快速反应极限下,涡旋干扰对燃烧气体流动的长时间影响,其中反应区厚度与最具代表性的湍流长度尺度相比显著较小。还收集了相反的慢反应极限的结果。反应性情况限于驱动爆震前沿不表现出自激振荡或固有不稳定性的情况。首先解决了平面爆震与单色扰动模式的相互作用,然后对三维各向同性湍流场进行傅里叶叠加,为下游动能、涡度和各向异性的放大提供积分公式。还为单频干扰提供了瞬态演化。此外,通过直接数值模拟研究了未包含在 LIA 中的与反应速率相关的进一步影响。基于 WENO-BO4 型方案的数值计算为四种不同情况提供了下游湍流传质结构的空间分布,其中包括非反应性冲击波、反应性不稳定冲击波(足够高的激活能)和不同爆震厚度的反应性稳定冲击波。分析了传播马赫数、化学反应热释放和燃烧速率的影响。