An experimental study of the effects of surface roughness on the laminar-turbulent transition of a 2D incompressible boundary-layer
| Autor: | Olivier Vermeersch, Estelle Piot, Maxime Forte, Felix Ducaffy |
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| Přispěvatelé: | ONERA / DMPE, Université de Toulouse [Toulouse], ONERA-PRES Université de Toulouse |
| Rok vydání: | 2021 |
| Předmět: |
[PHYS]Physics [physics]
Tollmien-Schlichting instabilities Materials science Boundary Layer Transition 02 engineering and technology Mechanics 01 natural sciences N-factor 010305 fluids & plasmas [SPI]Engineering Sciences [physics] Boundary layer Surface roughness 020303 mechanical engineering & transports 0203 mechanical engineering 0103 physical sciences Compressibility Laminar-turbulent transition |
| Zdroj: | AIAA Scitech 2021 Forum AIAA Scitech 2021 Forum, Jan 2021, Virtual event, United States. pp.AIAA 2021-0247, ⟨10.2514/6.2021-0247⟩ |
| DOI: | 10.2514/6.2021-0247 |
| Popis: | International audience; While it iswell known that increasing surface roughness tends to shift the transition location of a boundary-layer upstream, no model is currently able to accurately predict this shift as a function of the roughness parameters (mean roughness, skewness, etc.) for a transition driven by Tollmen-Schlichting instabilities. Moreover, the physics involved in this phenomenon is not well understood. Using a flat plate equipped with three exchangeable inserts whose roughness can be adjusted by 3D printing, experimental data are collected for different roughness values, different streamwise locations and different Reynolds numbers. The cases with rough inserts are systematically compared to the smooth reference cases and the Linear Stability Theory is used to estimate Delta_{N} values as a function of roughness parameters. These data constitute a first step towards a larger database which will make it possible to create a Delta_{N} model for the prediction of this effect. Hypotheses about the physical phenomena involved (changes in amplification and/or receptivity process) are proposed using the collected data. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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