高马赫数小尺度缝隙倒角热流测量

围绕再入式飞行器表面分布式隔热瓦的气动加热问题，针对流动强干扰特征且测量难度较大的小曲率半径缝隙倒角区域，采用Φ0.3 mm量级一体化同轴热电偶开展高马赫数来流条件下的热流测量，研究了缝隙倒角曲率半径、隔热瓦间台阶高度差、缝隙宽度、边界层流态、马赫数等因素对热环境的影响，通过分析热流时域曲线得到了瞬态热流的振荡特征。结果表明:台阶会显著增大热流；边界层流态的差异会引起缝隙倒角热流分布的显著变化；较高马赫数下的热流时域波动特征更温和，热流更低；部分状态存在瞬态负热流现象。 研究结果可为隔热瓦热防护设计和认识缝隙、台阶诱导的复杂流动机理提供参考。

Heat flux measurement of small scale gap corner at high Mach numbers

To investigate the aero-heating environment of distributed insulation tiles on re-entry flight vehicles, integrated coaxial thermocouples of only 0.3 mm in diameter are utilized to measure the heat flux at high Mach numbers. Intense interacted flow may prevail in interested regions such as the gap corner with small curvature radius. This makes it difficult to measure the heat flux. The curvature radius of the gap corner, height difference between insulation tiles, gap width, boundary layer state and Mach number are investigated to determine the influence on the aero-heating environment. Temporal signals are analyzed to obtain fluctuation characteristics of the transient heat flux. Results show that the inverse step leads to obvious heat flux rise. Difference in boundary layer state means notable discrepancy in the heat flux distribution over the gap corner. Higher Mach number induces less fluctuated heat signals and moderate heat flux. Negative heat flux phenomena emerges under some conditions. Results are useful to TPS design of insulation tiles, and increase the knowledge of the mechanism of the complex flow induced by gaps and steps.