Numerical study of two-airfoil arrangements by a discrete vortex method

Faure, Thierry; Dumas, Laurent; Montagnier, Olivier

doi:10.1007/s00162-019-00511-0

Cited by 17 publications

(7 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Undoubtedly, the surface roughness effect must be used to control this non-linear hydrodynamic phenomenon. This is one of important motivations for future extension of our present research, which will also include the study of slender body aerodynamics [7]. Another one is planned to investigate heat transfer behavior in mixed convection of a fluid by a temperature particles method [8].…”

Section: Introductionmentioning

confidence: 99%

Control and Suppression of Vortex Shedding from a Slightly Rough Circular Cylinder by a Discrete Vortex Method

et al. 2020

View full text Add to dashboard Cite

A discrete vortex method is implemented with a hybrid control technique of vortex shedding to solve the problem of the two-dimensional flow past a slightly rough circular cylinder in the vicinity of a moving wall. In the present approach, the passive control technique is inspired on the fundamental principle of surface roughness, promoting modifications on the cylinder geometry to affect the vortex shedding formation. A relative roughness size of ε*/d* = 0.001 (ε* is the average roughness and d* is the outer cylinder diameter) is chosen for the test cases. On the other hand, the active control technique uses a wall plane, which runs at the same speed as the free stream velocity to contribute with external energy affecting the fluid flow. The gap-to-diameter varies in the range from h*/d* = 0.05 to 0.80 (h* is the gap between the moving wall and the cylinder bottom). A detailed account of the time history of pressure distributions, simultaneously investigated with the time evolution of forces, Strouhal number behavior, and boundary layer separation are reported at upper-subcritical Reynolds number flows of Re = 1.0 × 105. The saturation state of the numerical simulations is demonstrated through the analysis of the Strouhal number behavior obtained from temporal history of the aerodynamic loads. The present work provides an improvement in the prediction of Strouhal number than other studies no using roughness model. The aerodynamic characteristics of the cylinder, as well as the control of intermittence and complete interruption of von Kármán-type vortex shedding have been better clarified.

show abstract

Section: Introductionmentioning

confidence: 99%

Control and Suppression of Vortex Shedding from a Slightly Rough Circular Cylinder by a Discrete Vortex Method

et al. 2020

View full text Add to dashboard Cite

show abstract

“…This leads to a simultaneous two-variable problem in the form where, and where is the downwash distribution induced by a unit-strength discrete vortex placed at the location of the latest-shed LEV. As noted by Faure, Dumas & Montagnier (2020), this approach eliminates the Newton-iteration procedure suggested by Katz & Plotkin (2000) and implemented previously by Ramesh et al. (2014), and easily extends to multiple lifting surfaces.…”

Section: Low-order Aerodynamic Modelmentioning

confidence: 95%

Theoretical and experimental investigation of an unsteady airfoil in the presence of external flow disturbances

et al. 2021

View full text Add to dashboard Cite

show abstract

“…The 2D LDVM is a reduced order unsteady flow simulation method around an airfoil which requires low computing power and short simulation time [30][31][32] . It is based on the thin airfoil theory and models the time-dependent vorticity distribution along the chord-wise x axis as a Fourier series 33 :…”

Section: Ldvm 1 2d Ldvmmentioning

confidence: 99%

Flapping wing propulsion: Comparison between discrete vortex method and other models

et al. 2022

Self Cite

View full text Add to dashboard Cite

Cetacean propulsion by a periodic flapping motion of their fluke is considered and studied on a benchmark flexible straight wing. The aim of the study was to validate low-order models for this configuration. First, the two-dimensional rigid case is investigated, comparing the aerodynamic performance of the airfoil periodic motion vs the reduced frequency, with published data and unsteady Reynolds-averaged numerical simulation results. It appears that viscous drag modeling must be added to the discrete vortex method, in order to obtain sensible thrust results, for Garrick frequencies below 2. All high- and low-order models agree at the remarkable Garrick frequency of 1.82, although the experiment shows a lower efficiency of about 25%. The positions of the shed vortices match comparing the unsteady Reynolds-averaged numerical simulation and the discrete vortex method. Then, the three-dimensional leading-edge-suction-parameter modulated discrete vortex method is extended, by means of a lifting line theory. A modification of the method is proposed in order to consider wing dihedral, resulting from the spanwise flexibility. The configuration considers a reduced frequency of 1.82. Three types of spanwise wing flexibility are examined. For the inflexible and flexible cases, a reasonable agreement is observed between the different methods for each coefficient. The intermediate flexible wing provides a better thrust coefficient, while excessive flexibility proves to be detrimental. Vorticity fields are compared with previously published data for the three wings. For the highly flexible wing and the right choice of deformation parameters, the discrete vortex method produces reliable results.

show abstract

Numerical study of two-airfoil arrangements by a discrete vortex method

Cited by 17 publications

References 43 publications

Control and Suppression of Vortex Shedding from a Slightly Rough Circular Cylinder by a Discrete Vortex Method

Control and Suppression of Vortex Shedding from a Slightly Rough Circular Cylinder by a Discrete Vortex Method

Theoretical and experimental investigation of an unsteady airfoil in the presence of external flow disturbances

Flapping wing propulsion: Comparison between discrete vortex method and other models

Contact Info

Product

Resources

About