Scientific Talk about Optimisation of a Multi-Element Airfoil at WESC2021
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- Опубликовано: 11 сен 2024
- Scientific talk about my master research project titeled "Computational Fluid Dynamic Analysis and Optimisation of a Multi-Element Airfoil for an Airborne Wind Energy System" at the Wind Energy Science Conference 2021 in Hannover.
WES research article:
wes.copernicus...
De Fezza, G. and Barber, S.: Parameter analysis of a multi-element airfoil for application to airborne wind energy, Wind Energ. Sci., 7, 1627-1640, doi.org/10.519..., 2022.
Authors:
Gianluca De Fezza
Dr. Sarah Barber
Your videos are so great sir!
Im doing some cfd for f1 wings, and Im facing some troubles
I have a 3 elements wing, but I don't know how to calculate the planform area
Should I adjust all the 3 elements to zero AoA, then taking the planform area?
Or should I consider all the 3 elements as 1 indivisual wing and then taking the planform area?
And if I did the second choice, should the equvalent wing be in zero AoA or what??
Im very confused!
I don't know which chord line to use and what are the conditions that should be achieved for the chord line
Please let me know
Hello and thank you for your comment. I guess, with planform area you mean the relevant reference area A of the wing. A = c t, where c is the airfoil chord length and t is the airfoil’s thickness.
Which choice you use for defining the chord length is up to you and which results you want to achieve. In my case, I did your second one, where I have measured the distance from the stagnation point of the main airfoil to the tailing edge of the second flap.
Regarding the AoA, you can decide yourself how you want to go with the naming. Theoretically, you could reference the AoA and have your 0° AoA where ever you want. But this is confusing. I did take the correct measured angle, so no confusion was created. That is also why the best AoA was around 25°.
In this kind of research, there is almost no right and wrong. Just go with what convinces and is best to work for you. Follow your thought and you will be fine.
Kind regards
@@gianlucadefezza6693
Thank you sir
That really helped me
Lloyds power ratio (LPR) is something I have never heard of. Would you please provide a reference to understand what LPR is? Unable to find anything ...
The useable power of an airborne wind energy system (P = 2/27 * rho * A * (CL^3 / CD^2) * v^3) is described in the Loyd's formula homes.esat.kuleuven.be/~highwind/wp-content/uploads/2011/07/Loyd1980.pdf. LPR is actually not yet widly used in literature and describes the aerodynamic performance of the airfoil, which is proportional to the power output of the airborne wind energy system (P ~ LPR). This means that LPR = CL^3 / CD^2 (CL = lift coeff.; CD = drag coeff.) and is the only variable and optimisable parameter (apart from A) in the Loyd's formula above. Some references, such as www.sciencedirect.com/science/article/abs/pii/S0960148117310285?via%3Dihub, do not call it LPR, but formulate it as P ~ E^2 * CL, where E = CL / CD is the glide ratio of the airfoil. Thus, in order to maximise the power output of an airborne wind energy system, LPR must be maximised.
PS: For more information on measuring performance output, see the recently published article (link in description).
Hello Gianluca, I have a question about changing the AoA of the whole wing (with flaps and strut). About which point are you rotating the whole wing? Is it the quarter-chord point of the main element or the quarter-chord point of the combined wing chord(line from main element leading edge to rear flap trailing edge)?
Hi Meto, the centre of rotation was always the stagnation point of the main wing and considered as stagnation point of the whole wing.
in which software did you do the simulation?
I‘ve used OpenFOAM V6.