water surface

new anne · January 9, 2012, 09:27

about modeling flow on spilways.when water flows it doesn't have a steady surface .in some places it seems like some small steps on face of the spillway.although i try very small ratio of meshinges,nothing happenes.i have no idea that what the solution is.could you plz help me.thanks.

JBurnham · January 13, 2012, 20:21

It depends on how you're analyzing the output. 2-D output will show the calculated surface exactly as it was calculated. 3-D output uses an approximation to create an iso-surface, and the approximation means that 3-D plots do not show the free surface perfectly. I suspect the little steps you're seeing are related to that 3-D approximation. View the spillway in 2-D to check.

January 9, 2012, 09:27	water surface	#1
new anne New Member Join Date: Dec 2011 Posts: 10 Rep Power: 15	about modeling flow on spilways.when water flows it doesn't have a steady surface .in some places it seems like some small steps on face of the spillway.although i try very small ratio of meshinges,nothing happenes.i have no idea that what the solution is.could you plz help me.thanks.

January 13, 2012, 20:21		#2
JBurnham Senior Member Jeff Burnham Join Date: Apr 2010 Posts: 204 Rep Power: 17	It depends on how you're analyzing the output. 2-D output will show the calculated surface exactly as it was calculated. 3-D output uses an approximation to create an iso-surface, and the approximation means that 3-D plots do not show the free surface perfectly. I suspect the little steps you're seeing are related to that 3-D approximation. View the spillway in 2-D to check. new anne likes this.

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