Hi,
I am trying to simulate a ship in a canal. The top width of the canal is 20m, bottom width is 6m, depth is less than 5m. Ship has a length of 11.7m breadth of 4m, draft is 0.62m. The velocity of the flat wave is given as 0.4m/s. Froude number is less than one (0.057). I am getting revered flow at times in the outlet, it vanishes as the simulation runs. I changed the pressure outlet to outlet condition to avoid reversed flow but the drag am getting is the same and its about 30N as it converges. But the problem is I am not getting proper wake effects (kelvin waves) in free surface. The software I am using is STARCCM+, K epsilon, implicit unsteady, VOF, DFBI are involved in the simulation.
Thanks in advance
A Froude number of 0.057 is very small. I suspect that viscosity might be damping out any waves created by the ship.
Have you tried running the nodel with a larger Froude number, e.g. 0.5?
Incidentally, your question has nothing to do with wakefulness, free will or personal autonomy, so please don't put those tags on your questions.
yes, I tried with Froude number 0.4 and I do get desirable wakes now. I think your observation is right. Thank you.
I didn't put those tags manually. will check on it in future.
Dear Dr. Anagha,
I think that you have deeper problem
and just find the wake (energy lost)
You assume that you have turbulence and yet you do not know if you have significant amount.
More than that, you are using software with fatal errors.
Basically you simulating solid liquid interactions where
you are using the wrong equations.
Let me list a partial list of the errors that you have.
1. Where is the pivot point of the ship for rolling?
you are using the wrong point (let me guess metacenter or mass centroid).
2. you are using the added mass matrix like A_{1,2} etc
This model violates the second law of thermodynamics.
3. You are not consider the added mass correctly
you neglect a major effect on the flow.
You should read the
https://www.researchgate.net/publication/372936982_A_Note_why_Added_Mass_Concept_is_Mathematically_Needed
I have not read or know exactly your idea but I have a strong guess what you are doing.
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