Response of NLF Airfoils to Small Scale Turbulence

Autor: Jonas Romblad, Ewald Krämer, W. Würz, Duncan Ohno, Amandine Guissart
Rok vydání: 2021
Předmět:
Zdroj: IUTAM Laminar-Turbulent Transition ISBN: 9783030679019
Popis: The effect of inflow turbulence level on the boundary layer transition on a Natural Laminar Flow (NLF) airfoil is investigated through detailed wind tunnel measurements. The free-stream turbulence level (\( Tu \)) is varied in the range \(0.01\%\le Tu \le 0.11\%\) by employing an active grid. Within the range of amplified TS-frequencies the spectral distribution of the \(u'\)-component could be matched to free flight measurements obtained for a glider at low to moderately turbulent conditions. Transition locations as function of turbulence level are determined for three airfoils with fundamentally different baseflows and the results are compared to the modified \(e^{9}\) method of Mack [6].
Databáze: OpenAIRE