journal article·2025-11-12Open access

Flow Visualization at Extremely Low Reynolds Numbers on NACA 0018 Airfoil with Bioinspired Tubercles

Ángel Antonio Rodríguez-Sevillano, Rafael Bardera-Mora, María Jesús Casati-Calzada, Juan Carlos Matías-García, Estela Barroso-Barderas, Jaime Fernández-Antón, Mirella Moreno-Ordóñez

Applied Sciences· Volume 15· Issue 22

Abstract

This study explores the aerodynamic behavior of bioinspired airfoils under extremely low Reynolds number conditions, simulating those found in the Martian atmosphere. Modified NACA 0018 profiles with sinusoidal leading-edge tubercles were tested to assess their influence on flow separation and overall aerodynamic performance. Experiments were carried out in a hydrodynamic towing tank using ink-based flow visualization, enabling detailed observation of the evolution of the separation point with varying angles of attack. The study focuses on comparing different tubercle configurations, analyzing how wavelength and orientation affect the aerodynamics of the airfoil. The results showed variations in flow stability and delayed separation compared to the baseline profile, indicating potential aerodynamic benefits. These findings offer valuable insights for the application of bioinspired geometries in the design of aerial platforms intended for Mars exploration and low-speed flight regimes, with special attention paid to Micro Aerial Vehicles (MAVs).
Source: crossref · Quality: baseline

Research context

OpenAlex topics: Biomimetic flight and propulsion mechanisms · Micro and Nano Robotics · Plasma and Flow Control in Aerodynamics

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Escuela Técnica Superior de Ingeniería Aeronáutica y del Espacio, Universidad Politécnica de Madrid, 28040 Madrid, Spain

Instituto Nacional de Técnica Aeroespacial (INTA), 28850 Torrejón de Ardoz, Spain

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