![]() ![]() Unsteady aerodynamic loads are compared with the corresponding static values. Dynamic simulations are carried out until the angle of attack goes past the lift stall point. A ramp function is used to smoothly increase the pitch rate from zero to the desired value and then held fixed. Good code-to-code agreement is observed for aerodynamic pressure- and skin friction coefficient distributions. Results of the static simulations are compared with XFOIL predictions as a sanity check. A static simulation is first carried out with each airfoil set at alpha = 4 degrees. A constant-rate pitch-up motion about the airfoil quarter-chord point is used to study dynamic stall. ![]() Three symmetric airfoils are studied with thickness-to-chord ratios of 9%, 12%, and 15%. The investigation is performed for three airfoils from the NACA family at Re c = 2 x 10 5. Large eddy simulations are used to investigate the effects of airfoil geometry, particularly thickness, on inception of dynamic stall. This makes me think that maybe at low incidences there is a trailing edge stall and then, going further, a leading edge stall. Looking at the pressure coefficient, there appears to be a laminar bubble very close to the leading edge (Figure 3).Īs the incidence increases, this bubble moves more and more towards the leading edge and, when $\alpha = 22°$, it "disappears". In fact, after the stall angle ( $\alpha_ = 11.0°$. The Benedek 10355 airfoil has a thickness of 10.1%.įigure 1 shows the polar calculated with Xfoil at Reynolds number = 500,000.Īnalyzing this curve, and comparing it with this answer, it seems to me that we are in the presence of a trailing edge stall. ![]() As I wrote last week, I'm doing a Benedek 10355 airfoil performance report.Īt this point of the work I am analyzing the stall of the profile at a fixed Reynolds number. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |