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This paper presents a comprehensive numerical investigation of a NACA0012 undergoing Stall Flutter Limit Cycle Oscillations (LCO) across distinct fluid dynamics regimes. It accurately models Small Amplitude Oscillations (SAO) in the…

Fluid Dynamics · Physics 2026-01-16 Nikos Spyropoulos , Marinos Manolesos , George Papadakis

The tendency of a jet to stay attached to a flat or convex surface is called the Coand\u{a} effect and has many potential technical applications. The aim of this thesis is to assess how well Computational Fluid Dynamics can capture it. A…

Computational Engineering, Finance, and Science · Computer Science 2021-10-06 Florent Mauret

This study employs Deep Reinforcement Learning (DRL) for active flow control in a turbulent flow field of high Reynolds numbers at $Re=274000$. That is, an agent is trained to obtain a control strategy that can reduce the drag of a cylinder…

Fluid Dynamics · Physics 2024-12-23 Jingbo Chen , Enrico Ballini , Stefano Micheletti

The flow over a NACA0012 airfoil at a moderate Reynolds number Re = 50,000 and angle of attack of alpha = 3 degrees is investigated using the lattice-Boltzmann method (LBM). The LBM solutions are computed in direct numerical simulation…

Fluid Dynamics · Physics 2024-11-08 Bernardo Luiz Ribeiro , Cayan Dantas , William Wolf

With growing interest in space exploration, optimized airfoil design has become increasingly important. However, airfoil design in rarefied gas flows remains underexplored because solving the Boltzmann equation formulated in a six…

Fluid Dynamics · Physics 2025-12-09 Xiaoda Li , Ruifeng Yuan , Yanbing Zhang , Lei Wu

In this paper, we discuss selected adjoint approaches for the turbulent flow control. In particular, we focus on the application of adjoint solvers for the scope of noise reduction, in which flow solutions are obtained by large eddy and…

Optimization and Control · Mathematics 2018-05-01 Emre Özkaya , Nicolas R. Gauger , Daniel Marinc , Holger Foysi

The dynamical response of an aircraft subject to gust perturbations is a key element in a preliminary design phase. In particular, the loads induced by gusts along the wing should not exceed some limit values and should even ideally be…

Systems and Control · Electrical Eng. & Systems 2021-07-05 Pierre Vuillemin , David Quero Martin , Charles Poussot-Vassal

Three-dimensional control is considered in the flow past a backward-facing step (BFS). The BFS flow at Reynolds number $Re=500$ (defined with the step height and the maximum inlet velocity) is two-dimensional and linearly stable but…

Fluid Dynamics · Physics 2020-08-12 E. Yim , I. Shukla , F. Gallaire , E. Boujo

In this paper, we study efficient and robust computational methods for solving the security-constrained alternating current optimal power flow (SC-ACOPF) problem, a two-stage nonlinear optimization problem with disjunctive constraints, that…

Optimization and Control · Mathematics 2023-08-11 Amin Gholami , Kaizhao Sun , Shixuan Zhang , Xu Andy Sun

Reynolds-Averaged Navier-Stokes(RANS) method will still play a vital role in the following several decade in aerospace engineering. Although RANS models are widely used, empiricism and large discrepancies between models reduce the…

Fluid Dynamics · Physics 2018-07-05 Weiwei Zhang , Linyang Zhu , Yilang Liu , Jiaqing Kou

A novel method to estimate unsteady aerodynamic force coefficients from pointwise velocity measurements is presented. The methodology is based on a resolvent-based reduced-order model which requires the mean flow to obtain physical flow…

Fluid Dynamics · Physics 2016-09-21 F. Gómez , A. S. Sharma , H. M. Blackburn

Direct numerical simulations (DNS) of rotating pipe flows up to $Re_{\tau} \approx 3000$ are carried out to investigate drag reduction effects associated with axial rotation, extending previous studies carried out at a modest Reynolds…

Fluid Dynamics · Physics 2024-07-29 Maochao Xiao , Alessandro Ceci , Paolo Orlandi , Sergio Pirozzoli

Uniform flow distribution across parallel channels directly impacts the performance and efficiency of many fluid and energy systems. However, designing efficient flow manifolds that ensure uniform flow distribution remains a challenge. This…

Fluid Dynamics · Physics 2025-10-06 Sanjay Vermani , Nitish Anand

This study concerns the far-field boundary conditions (BCs) for airfoil simulations at high incidence where the lift and drag are comparable in magnitude and the moment is significant. A NACA 0012 airfoil was simulated at high Reynolds…

Fluid Dynamics · Physics 2024-11-21 Narges Golmirzaee , David H. Wood

We perform unsteady three-dimensional direct numerical simulations to study the aerodynamic characteristics of finite-aspect-ratio swept wings with a NACA 0015 cross-section at a chord-based Reynolds number of 400. The effects of the sweep…

Fluid Dynamics · Physics 2020-11-26 Kai Zhang , Kunihiko Taira

The aeroacoustics of a NACA 0012 aerofoil with an array of self-oscillating flexible flaplets attached on the trailing edge has been investigated at low to moderate chord based Reynolds number (50,000 -- 350,000) and at geometric angles of…

Fluid Dynamics · Physics 2020-01-08 E. Talboys , T. F. Geyer , C. Bruecker

Wing-body junction flows occur when a boundary layer encounters an airfoil mounted on the surface. The corner flow near the trailing edge is challenging for the linear eddy viscosity Reynolds Averaged Navier-Stokes (RANS) models, due to the…

Fluid Dynamics · Physics 2016-05-20 Jin-Long Wu , Jian-Xun Wang , Heng Xiao

Real-time and accurate prediction of aerodynamic flow fields around airfoils is crucial for flow control and aerodynamic optimization. However, achieving this remains challenging due to the high computational costs and the non-linear nature…

Fluid Dynamics · Physics 2025-10-23 Chunyang Wang , Biyue Pan , Zhibo Dai , Yudi Cai , Yuhao Ma , Hao Zheng , Dixia Fan , Hui Xiang

This paper discusses the design and the performance achievable with active aerodynamic attitude control in very low Earth orbit, i.e. below 450 km in altitude. A novel real-time algorithm is proposed for selecting the angles of deflection…

This work focuses on the numerical assessment of the accuracy of an adjoint-based gradient in the perspective of variational data assimilation and parameter identification in glaciology. Using noisy synthetic data, we quantify the ability…

Classical Physics · Physics 2014-03-11 Nathan Martin , Jérôme Monnier