Dynamic Stall Simulations on a Pitching Finite Wing

2017 ◽  
Vol 54 (4) ◽  
pp. 1303-1316 ◽  
Author(s):  
Kurt Kaufmann ◽  
Christoph B. Merz ◽  
Anthony D. Gardner
Keyword(s):  
2019 ◽  
Vol 64 (3) ◽  
pp. 1-13 ◽  
Author(s):  
A. D. Gardner ◽  
C. B. Merz ◽  
C. C. Wolf

An investigation was performed into the effect of positive and negative sweep angle on the boundary layer transition and dynamic stall behavior of a finite wing. The finite wing had a 6:1 aspect ratio, modern (SPP8) tip shape, and positive twist, moving the maximum load on the wing away from the wind tunnel wall. Experiments were performed with sweep Λ = ±30° and Λ = 0° for static polars and sinusoidal pitching. The positively twisted wing shows a S-shaped boundary layer transition on the pressure side similar to that previously seen for helicopter rotor blades in hover. The transition positions on the suction side of the wing are comparable for the same local angle of attack at all values of the sweep at each of the three pressure sections, and for dynamic pitching motions a hysteresis around the static transition positions is seen. Sweeping the wing led to later stall and higher maximum lift for both static polars and dynamic stall, except for a single case. The negative aerodynamic damping is worse for the swept wing than for the unswept wing, except where the delay of stall led to the flow remaining attached.


2019 ◽  
Vol 9 (3) ◽  
pp. 600 ◽  
Author(s):  
Qing Wang ◽  
Qijun Zhao

To study the three-dimensional effects on the dynamic-stall characteristics of a rotor blade, the unsteady flowfields of the finite wing and rotor were simulated under dynamic-stall conditions, respectively. Unsteady Reynolds-averaged Navier–Stokes (URANS) equations coupled with a third-order Roe–MUSCL spatial discretization scheme were chosen as the governing equations to predict the three-dimensional flowfields. It is indicated from the simulated results of a finite wing that dynamic stall would be restricted near the wing tip due to the influence of the wing-tip vortex. By comparing the simulated results of the finite wing with the spanwise flow, it is indicated that the spanwise flow would arouse vortex accumulation. Consequently, the dynamic stall is restricted near the wing root and aggravated near the wing tip. By comparing the simulated results of a rotor in forward flight, it is indicated that the dynamic stall of the rotor would be inhibited due to the effects of the spanwise flow and Coriolis force. This work fills the gap regarding the insufficient three-dimensional dynamic stall of a helicopter rotor, and could be used to guide rotor airfoil shape design in the future.


1999 ◽  
Vol 103 (1023) ◽  
pp. 229-236 ◽  
Author(s):  
F. N. Coton ◽  
R. A. McD. Galbraith

Abstract This paper examines the dynamic stalling of a finite wing of aspect ratio 3·0 when subject to constant pitch motions up to and beyond stall. In particular, unsteady surface pressure data were obtained at 192 locations on the wing surface and these were then analysed to provide information on the nature and phasing of dynamic stall events in both the chordwise and spanwise directions. It was also possible to obtain sectional force and moment coefficients by integration of the pressures measured on specific chordal arrays. This provided valuable insight into the load distribution on the wing throughout the range of motion. On this basis, it was established that the wing loading distribution was consistent with conventional understanding of steady wing loading up to the incidence at which the dynamic stall vortex was initiated. Beyond this point, the formation and subsequent convection of the vortex structure was found to be strongly three-dimensional but, nevertheless, exhibited many of the features of two-dimensional dynamic stall.


2021 ◽  
Author(s):  
Patrick R. Hammer ◽  
Daniel J. Garmann ◽  
Miguel Visbal

2001 ◽  
Vol 105 (1045) ◽  
pp. 151-159 ◽  
Author(s):  
F. N. Coton ◽  
R. A. McD. Galbraith ◽  
R. B. Green

AbstractThis paper examines the dynamic stalling of three wing planforms and characterises the main features of the stalling process in each case. The particular data were obtained during a three year research programme in the Department of Aerospace Engineering, University of Glasgow to collect high-resolution unsteady pressure data on the dynamic stalling characteristics of finite wing planforms. In this study, which was motivated by the pressing need for a greater understanding of the strongly three-dimensional effects in the tip region of helicopter rotors, the three wing planforms considered were a straight rectangular wing, a rectangular wing with swept tips and a delta wing. The initial test programme was followed by a further three years of detailed analysis and interpretation of the test data. Results from this analysis are presented in the present paper for cases in which the wings were subject to ramp motions.


AIAA Journal ◽  
2019 ◽  
Vol 57 (7) ◽  
pp. 2722-2733 ◽  
Author(s):  
Ignacio Andreu Angulo ◽  
Phillip J. Ansell

2019 ◽  
Author(s):  
Matthew Rockwood ◽  
Albert Medina ◽  
Daniel J. Garmann ◽  
Miguel R. Visbal
Keyword(s):  

2015 ◽  
Vol 60 (3) ◽  
pp. 1-12 ◽  
Author(s):  
Kurt Kaufmann ◽  
Michel Costes ◽  
François Richez ◽  
Anthony D. Gardner ◽  
Arnaud Le Pape

Sign in / Sign up

Export Citation Format

Share Document