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kegiljarhus / pyBEMT

Implementation of the Blade Element Momentum Theory for turbines and propellers in Python
MIT License
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Adding 3D correction (stall delay model) #3

Closed EngenMe closed 1 year ago

EngenMe commented 2 years ago

The classical BEMT is not designed to account for flow three-dimensionality as no interaction between each blade section to the neighboring sections is assumed in the model. Thus, the approach depends strongly on the supplied aerodynamic polars. Due to this limitation, the 3D effects shall be stimulated in the given polars. In the present works, the 3D correction model based on Chaviaropoulos and Hansen is used. The model was developed by adopting the idea from Snel to express the 3-D correction of the lift coefficient CL as a fraction of the difference (∆CL) between the inviscid (C(l,inv)) and the corresponding 2-D value (C_(L,2D)). In this model, the influence of twist angle is introduced in the ∆CL multiplier. The model can be formulated as follows: .. math:: Cl_3D = Cl_2D + a (c / r)^h \cos^n{twist} (Cl_inv - Cl_2d) \ Cl_inv = \sqrt{Cl_2d^2 + Cd^2} where: a = 2.2, h = 1.3 and n = 4 :param float phi: Inflow angle :return: Lift coefficient with 3D correction :rtype: float .. bib:: @article{chaviaropoulos2000investigating, title={Investigating three-dimensional and rotational effects on wind turbine blades by means of a quasi-3D Navier-Stokes solver}, author={Chaviaropoulos, PK and Hansen, Martin OL}, journal={J. Fluids Eng.}, volume={122}, number={2}, pages={330--336}, year={2000} } the two figures shows the power and thrust coefficients compared to the experimental results for the case of APC 10x7 propeller. The first without 3D correction, and the second with a 3D correction. We can see the small changes in error at J = 0.7 image image

kegiljarhus commented 1 year ago

Thank you for the addition of a 3D correction model. Could you please also add the case files for the APC 10x7 propeller test case?

EngenMe commented 1 year ago

Dear Dr. Knut

I am working to add the all the APC propellers to this project. In addition, I have a good project to predict the aerodynamic forces around a propeller using artificial intelligence.

I trust this finds you well and sound.

Please find attached some results of CT and CP compared to the experimental ones.

Now, I am really interest about the PhD position in the University of Stavanger link

https://www.jobbnorge.no/en/available-jobs/job/232069/phd-fellowship-in-computational-fluid-dynamics-and-drill-string-mechanics

I have all the skills mentioned for this position, my background of math and fluid dynamics is good, I got the full note in the exam of numerical methods, hight computing skills, I can work with multiple programming languages, and I am good in machine learning and data driven. In addition, I have all papers necessary to apply, but I don't have the English language test yet, I prepare to pass the IELTS next month, you can find my cv attached below.

If you can support me in this application, I will be pleased Dr.

Kind regards M. Farouk Hasnaoui

On Mon, Oct 24, 2022, 11:08 Knut Erik T. Giljarhus @.***> wrote:

Merged #3 https://github.com/kegiljarhus/pyBEMT/pull/3 into master.

— Reply to this email directly, view it on GitHub https://github.com/kegiljarhus/pyBEMT/pull/3#event-7652485672, or unsubscribe https://github.com/notifications/unsubscribe-auth/AT4NFVRSBGYPZ3KYHWDQQDTWEZNYZANCNFSM5ZDNU7ZA . You are receiving this because you authored the thread.Message ID: @.***>

kegiljarhus commented 1 year ago

Please send me an e-mail instead, knut.e.giljarhus@uis.no