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what does the black mean?

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Old   September 2, 2009, 11:56
Default what does the black mean?
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The ball is a porous ball, there are a lot of pores inside and outside of it. But in the results, i saw many places especally inside of the ball the color is black, what does the black mean?
no flow? no velocity? or what?
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Old   September 2, 2009, 16:41
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Chris
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Originally Posted by poiu View Post
The ball is a porous ball, there are a lot of pores inside and outside of it. But in the results, i saw many places especally inside of the ball the color is black, what does the black mean?
no flow? no velocity? or what?
It looks like it might be that the values for velocity in that region are out of the range that you set. See the pictures below. When the values of the flow parameter that you're plotting are out of the range of the contour plot, the regions that contain these values are displayed as black. So, in your case, is the velocity in those regions less than zero?
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Old   September 3, 2009, 20:54
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Hello,

I had the same initial thought as Chris, but after I think about it I think that fluent gives you absolute values for velocity magnitude in the contour plots, so you shouldn't have negative values. Unless the values are outside of the upper limit (which would be odd in that location) they should show up in the sphere. What do the vectors and pressure contours look like? It couldn't hurt to play with the ranges for the contour plot like Chris suggested, too.

-sean
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Old   September 6, 2009, 09:10
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Originally Posted by Chris D View Post
It looks like it might be that the values for velocity in that region are out of the range that you set. See the pictures below. When the values of the flow parameter that you're plotting are out of the range of the contour plot, the regions that contain these values are displayed as black. So, in your case, is the velocity in those regions less than zero?

thank you very much!
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Old   September 6, 2009, 09:11
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Originally Posted by delfel View Post
Hello,

I had the same initial thought as Chris, but after I think about it I think that fluent gives you absolute values for velocity magnitude in the contour plots, so you shouldn't have negative values. Unless the values are outside of the upper limit (which would be odd in that location) they should show up in the sphere. What do the vectors and pressure contours look like? It couldn't hurt to play with the ranges for the contour plot like Chris suggested, too.

-sean
thank you very much!
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Old   September 6, 2009, 09:24
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i have another question:
The model is about a porous granule moving in an infinite fluid, i set the velocity of the fluid, and make the surface of the porous granule to be interface, but after i set the interface in FLUENT, there appeared two walls in the place of the interface, and the results you can see in the picture, the velocity of the surface of the granule is zero. i think it's wrong, but i don't know how to change it. i need your help,thank you !
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