摘要
基于C/SiC复合材料的被动氧化模型,研究了氧化界面表面分形维数、高度比例系数与频率因子对氧化交界面形貌的影响。通过Weierstrass-Mandelbrot(W-M)函数模拟氧化层与复合材料层的交界面形貌,并计算分析了不同参数对界面特征的影响。研究结果表明,所建立模型重构的氧化交界面的最大差量与实验测量结果相符;表面分形维数和高度比例系数主要影响特征高度,且其值越大,界面粗糙度越显著;此外,频率因子对重构界面的凸起数量及沿特征长度方向的生成频率亦具有显著影响。最后提出通过控制C/SiC复合材料中C组分的比例及其分布延迟高超声速边界层转捩。数值模拟结果表明,周期分布C组分比例为0.27~1的C/SiC复合材料形成的波纹状氧化层有效抑制了边界层第2模态的增长,达到降热减阻的效果。
Utilizing the passive oxidation model of the C/SiC composite,an investigation was conducted into the impacts of fractal dimension,height scale factor,and frequency factor on the morphology of the oxidation interface.The oxide layer and composite layer interface morphologies were simulated using the Weierstrass-Mandelbrot(W-M)function,and the ramifications of varying parameters on interface characteristics were quantitatively analyzed.The findings indicate that the maximum discrepancy in the oxidation interface reconstructed by the proposed model aligns well with experimental measurements.Specifically,the surface fractal dimension and height scale coefficient predominantly influence the feature height,where higher values result in more pronounced interface roughness.Furthermore,the frequency factor exhibits a notable influence on the number of bumps and the generation frequency along the characteristic length direction of the reconstructed interface.Finally,it was proposed to delay the transition of the hypersonic boundary layer by controlling the proportion and distribution of C components in C/SiC composite materials.Numerical simulation results indicate that a wavy oxide layer formed by C/SiC composites with a periodically distributed C component ratio ranging from 0.27 to 1 effectively suppresses the growth of the second mode instability in the boundary layer,thereby reducing both heat and drag.
作者
麻连俊
范良忠
朱庆勇
MA Lianjun;FAN Liangzhong;ZHU Qingyong(School of Aeronautics and Astronautics Sun Yat-sen University,Shenzhen 518107,China)
出处
《气体物理》
2025年第1期1-14,共14页
Physics of Gases
