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Dear all,
I would like to study the wind effect in my problem. I saw in the validation test, v6p2 (problem number 038 wind) that the COEFFICIENT OF WIND INFLUENCE (avent) was 1.2615E-3. However, in the telemac user manual (page 54) I understood that value must be devided by 1000 (that means COEFFICIENT OF WIND INFLUENCE=1.2615E-6 in my steering file). Is that right? Thank you very much for your guide.
Best regards
Thong NGUYEN
HCMUT, VN

Hello

COEFFICIENT OF WIND INFLUENCE =

(air density/water density) * CD

Where

air density ~ 1.023
water density ~ 1000
CD is what is usually called wind drag coefficient

So the values you see for CD must be multiplied by the ratio shown above.

Hope it helps

Mathieu

Hello,
Thank you very much for your prompt response. With your suggestion, that means the value COEFFICIENT OF WIND INFLUENCE =1.2615E-3 used in steering file of validation test of v6p2 (number 038 wind) was wrong (too big?) ? (see telemac-2d_user_manual_en_v6p2.pdf page 54). The reasonable value must be declared in steering file is : COEFFICIENT OF WIND INFLUENCE =1.023/1000*1.2615E-3=1.262E-06 (for example 5m/s<Wind<19.22m/s), that's right?
Best regards
Thong NGUYEN
HCMUT, VN

Hello,

In the validation case "wind" of Telemac2D, the coefficient is artificially increased in order to show clearly the wind effect. Actually, with real (physical) coefficients, the wind effect can be negligeable compared to other phenomena.
Therefore, the coefficient you need to introduce for this key-word has to be in the same rough size of 10-6.

With my best regards

Riadh ATA

Hello,
Thank you very much for your explain.
Best regards
Thong NGUYEN
HCMUT, VN