Oil Film Interferometry

Abstract

This study investigates the use of Oil Film Interferometry (OFI) as a method to measure wall shear stress (WSS) in fluid dynamics. By applying this technique to a flat plate in a subsonic wind tunnel, the study aims to validate OFI’s accuracy across different Reynolds numbers and assess its effectiveness in capturing boundary layer transitions from laminar to turbulent flow. The research explores how varying the thickness of tripping discs impacts the boundary layer, with validation values obtained from OFI used to assess the transition behavior when tripping is applied. The findings confirm the reliability of OFI for measuring skin friction and highlight how changes in disc thickness affect transition points and skin friction measurements. These insights are valuable for improving aerodynamic efficiency through enhanced boundary layer control.