How does Star CCm+ evaluate the wave lenght of wave when we indicate the value of the

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October 9, 2018, 11:07
How does Star CCm+ evaluate the wave lenght of wave when we indicate the value of the
#1
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Join Date: Sep 2018
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Hello Guys,
I realise all the steps until where i have to indicate the wave lenght or the period of the wave.
Usually i just indicate the wave lenght, but i want to know how Star ccm+ evaluate the lenght of wave when you indicate the period.
I ask that beacause when i try with the data : T=5.5s and the depth d=100m, it give me the wave lenht of 227.8m; problem is , when i use the formula indicate in the tutorials, i mean the relation of dispersion, i never find the same result. What is the problem , since Star have indicated theorically how to calculate it.
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 October 9, 2018, 12:30 #2 Senior Member   Sebastian Engel Join Date: Jun 2011 Location: Germany Posts: 566 Rep Power: 19 Hi Brice, i checked the manuel for that section. Did you notice, that actually the whole set of equations for fifth order waves are not given? Only for first order waves equations are given. You might have to work though the stated paper to get the correct formula. You'll find it via google and alikes. In the section application of theory, point 3 is probably what you are looking for. Best regards, Sebastian

October 10, 2018, 05:21
#3
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Join Date: Sep 2018
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Quote:
 Originally Posted by bluebase Hi Brice, i checked the manuel for that section. Did you notice, that actually the whole set of equations for fifth order waves are not given? Only for first order waves equations are given. You might have to work though the stated paper to get the correct formula. You'll find it via google and alikes. In the section application of theory, point 3 is probably what you are looking for. Best regards, Sebastian

Hello Sebastian,
You were right.
I effectly did read that there were something with the fifth order of wave, but i didn't want to look deep into it.
Now, i did read the paper by John Fenton, where Star took the formula, and then i did find the same result.

 November 16, 2018, 02:46 #4 New Member   Join Date: Jul 2018 Posts: 4 Rep Power: 6 Hi Brice. May i ask u something? i am also doing simulation of boat in a head wave with a speed of 20knots that equal to 10.2888m/s. based on your experience where did you put the 10.2888m/s(velocity) value. at the velocity node of DFBI node or at the current and wind of head wave node.