Investigation Of The Skin Friction Measurement Using Oil Film Interferometry

In this paper, the oil film interferometry has been used to measure the skin friction of a flat platemodel, airfoil model and wing model, the applicability and operating methods of the oil film interfe-rometry on the flat surface and curved surface are explored. Some problems of the different ways us-ing oil film interferometry are studied. The test error are also been analyzed. The result show that, onthe flat surface, the influence of model installation, oil film distribution and gravity on the oil filminterferometry could be negligible and the experiment data could be processed by the original formu-las directly. On the curved surface, in order to get the results more accurate, the model installation andoil film distribution should be designed, and some parameters should be amended. Using the oil filminterferometry to measure the skin friction of the wing model not only can analyze the characteristicsof the surface flow field, but also can get the result of skin friction. In this paper, hot-film method andvelocity profile method have been also used to measure the skin friction as comparison. the oil filminterferometry can be used to the skin friction measurements in the flight test and the high speed windtunnel test.