Investigations of influence of Free Stream Turbulence and Acoustic Disturbances on the Laminar-Turbulent Transition on LV6 Airfoil and Swept Wing Models

Abstract

The main objective of the work was to generate the data that could be used for quantitative evaluation of free-stream turbulence level and noise influence on laminarturbulent transition. Series of experiments were performed in TsAGI T-124 low turbulence wind tunnel to analyze these effects. The flows over laminar airfoil and swept wing models were investigated. The experiments were carried out at free-stream velocity of 80 m/s. To increase initial flow turbulence level, the turbulizing grids were used. All measurements were accomplished using the hot-wire anemometer. The stability characteristics of laminar boundary layers on airfoil and swept wing models for T-124 wind tunnel experimental conditions were calculated on the basis of linear stability transition prediction method. The values of N-factor corresponding to experimental transition location at various free-stream turbulence levels and acoustic disturbances for both models were obtained.