Study on the effect of raindrops on the dynamic stall of a NACA-0012 airfoil

• Main Authors: Salavatidezfouli, S. (Author), Schito, P. (Author), Sheidani, A. (Author)
• Format: Article
• Language: English
• Published: Springer Science and Business Media Deutschland GmbH 2022
• Subjects: Aerodynamic stalling; Airfoils; Discrete phase model; Discrete phase model (DPM); Discrete phase modeling; Dispersed multiphase; Dispersed multiphase (DMP); Drops; Dynamic stall; Dynamic stalls; Lagrange multipliers; Model-based OPC; Multiphase modeling; Multiphases; ON dynamics; Pitching airfoil; Pitching airfoils; Rain; Reynold number; Reynolds number; Vortex flow
• Online Access: View Fulltext in Publisher

 In this study the pure effect of raindrops on dynamic stall of a pitching airfoil has been investigated. The simulation was performed at Reynolds number of 10 6 with raindrop diameter equal to 10 - 5m. A couple of multiphase models based on Eulerian and Lagrangian frames of reference have been implemented to simulate the raindrops. In the first step the accuracy of each multiphase model has been appraised. As a result, the Lagrangian multiphase model, which is called Discrete Phase Model, has been proven to be of better accuracy. It has been concluded that in general raindrops has negative effects on the lift coefficient of the pitching airfoil. In addition, a lead in aerodynamic phenomena has been observed due to the presence of water drops. This phenomenon has also been observed in the formation and separation of Leading Edge and Trailing Edge vortices which come to existence in advance of the dry case. Finally, it has been illustrated that the main effect of raindrops is on the phase of force oscillation rather than the force amplitude. © 2022, The Author(s).