Abstract:
Luminescent oil flow technique is a way of measuring global skin friction. This technique is developed on the basis of traditional luminescent oil flow method. It is a visible measurement technique extracting original experiments data by using traditional luminescent oil flow. These data are further processed by HS optical flow algorithm to obtain the surface model of oil film thickness variation on temporal axis. The thickness variation indicates the local relative surface skin friction according to the momentum theorem. In this paper, we used this measurement technique to diagnose the skin friction distributions of a flat plate, a 75°delta wing and a junction model in low speed wind tunnel. The distributions of relative friction and the friction line were also achieved. A comparison was shown between the plate model Blasius laminar flow solutions and classic flow structure of the delta wing model. The test results indicate that this visible skin friction measurement method can be used to provide skin friction information conveniently and uniquely in low speed wind tunnel experiments.