Identification of the Boundary Layer Shock Wave Interaction Type in Transonic Flow Regime

Abstract

The paper presents various approaches to wind tunnel data analysis when identifying the shock wave boundary layer interaction type. The investigation was carried out in the transonic flow regime in the N-3 Wind Tunnel of Institute of Aviation. The Mach number was 0.7 and Reynolds number was approximate equal 2.85 million. The object of the research was a laminar airfoil in configuration without and with turbuliser device mounted on the upper model surface. In order to achieve turbulent boundary layer in front of the shock wave the carborundum strip was used. The effect of the varying angle of incidence on the flow filed was investigated. During experimental research, different means and test methods were applied (pressure measurements, Schlieren and oil visualisation, Particle Image Velocimetry (PIV), hot-film anemometry). The results were analysed in terms of the shock wave boundary interaction type. Most of results were in good agreement with theoretical models reported in the literature. The study showed that combination of various measurement techniques should be used in the shock wave boundary investigations in order to achieve more consistent and reliable conclusions. The results of the presented research can also be used for better understanding other mechanisms i.e. the boundary layer shock wave separation process in transonic flow regime.

Turbulent Triggers and the Model Quality Influence on Aerodynamic Characteristics of the Laminar Aerofoil in Transonic Flow Regime

“…For the baseline, Final_v2(polished) model configuration the laminar character of SWBLI was maintained at higher incidence, in contrast to the Pre-test model. The identification methods of the SWBLI type, related to current study, were described in [4]. Drag coefficient Drag coefficient value of the Final_v2(polished) model in baseline and carborundum configuration was presented in Tab.…”