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Moment Center and Moment Axis as a function on flow-time

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Old   February 1, 2019, 08:14
Default Moment Center and Moment Axis as a function on flow-time
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Federico
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Dear all,
I am currently working on a sliding mesh set-up involving the simulation of the flow passing through a tidal turbine. One thing I am struggling with is how to monitor the moment of a force in such a problem:
At each time step (if I refer to a blade) I have that Moment center coordinates and moment axis components are changing.

I tackled this aspect by typing on execute command text line the following:

(define t (rpgetvar 'flow-time)) (define omega 7.644542) solve/monitors/force/set-moment-monitor cm-x y 28 33 , y y /Path/to/cx1.txt n n (* 0.036 (sin (* omega t))) (* 0.036 (cos (* omega t))) 0 (- 0 cos (* omega t)) (sin (* omega t)) 0

The following warning and errors appears although a cx1.txt file is outputted:

(define t (rpgetvar 'flow-time))
t
(define omega 7.644542)
omega

Error: + (add): invalid argument [1]: wrong type [not a number]
Error Object: #[primitive-procedure cos]
solve/monitors/force/set-moment-monitor cm-x y 28 33 , y y /Path/to/cx1.txt n n (* 0.036 (sin (* omega t))) (* 0.036 (cos (* omega t))) 0 (- 0 cos (* omega t))Invalid real.
(sin (* omega t)) 0
z-component of moment axis [0]

Anybody knows what this Errors mean?
I would like to stress the fact that a file ( cx1.txt) was written!
Do you think the aforementioned mathematical expression was calculated?


Hope you can help me with this!!
Thank you in advance

Best regards,

eeLio
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Old   February 1, 2019, 10:40
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Quote:
Originally Posted by eeLio View Post
solve/monitors/force/set-moment-monitor cm-x y 28 33 , y y /Path/to/cx1.txt

I think the issue is this comma , appearing here but I can't really tell because I don't know your entire case setup. Just go into Fluent and manually type in solve/monitors/force/set-moment-monitor and then follow the prompts.
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