Study of Skin Friction Stress Measurement Technique Based on Oil Film Interferometry
基于油膜干涉法的表面摩擦应力测量技术研究

Oil film interferometry and velocity profile method were used to measure skin friction stress of a flat plate model in low-speed turbulence. Skin friction measurement technique based on oil film was explored. The influence of different experimental methods on measurement results and the cause of experimental errors were analyzed. Results show that the influence of model installation, oil film arrangement and gravity in oil film interferometry may be neglected, and the experiment data may be processed by the original formulas directly in the case of low precision requirement. Skin friction of an airfoil was measured by using both oil film interferometry and hot-film. Results indicate that oil film interferometry is an experimental technique with extensive application in wind tunnel, and may be applied in high-speed wind tunnel and large transport aircraft flight experiment.