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June 8, 2011, 07:15 
Function integral over time

#1 
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Andrew
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Tell me please, is there any possibility to use Ansys CFX time as a parameter in the formulation of transients problems. In the standard features you can not take the time integral. Is there a function integral over time? Or subroutine, which allows to produce a similar action. I'll be very grateful to you for any help in my problem.


June 8, 2011, 08:06 

#2 
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Glenn Horrocks
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What do you want to take the time integral of?


June 9, 2011, 03:37 

#3 
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Andrew
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For use as a criterion for stopping the calculation


June 9, 2011, 06:51 

#4 
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Glenn Horrocks
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Sure  note there are already lots of stopping criterion built in so are you sure you need to implement your own?
But what do you need to do the time integral of? 

June 9, 2011, 08:01 

#5 
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Andrew
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For example, we put on the surface of the paint brush, and we want to calculate what weight we are already done. In fact, we can change the flow of paint in each time, so I want to know how much paint has been applied to the desired point in time. That is the problem confined to the creation of a counter weight of the paint to a certain time.
Or the inverse problem  we have a certain volume of paint, we are doing with various pitch. How much does it for painting? 

June 9, 2011, 08:13 

#6 
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Glenn Horrocks
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Arrgh! I did not ask for an example of a time integral, I know very well what time integral is.
What variable do you want to take the time integral of? 

June 10, 2011, 06:33 

#7 
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Andrew
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Heat flow, for a problem with the heat flow


June 10, 2011, 06:44 

#8 
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Glenn Horrocks
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The time integral of a heat flow is the increase/decrease in heat. So you can do a volume integral of the heat in the domain. No need for a time integral.


June 11, 2011, 03:48 

#9 
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Andrew
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The task is nextpassing the source of thermal radiation with respect to products with it must be removed a certain number of particles. The rate of passage may vary. The number of these particles we want to calculate. Or calculate the time spent checkpoint in a spot source, which is the same. It is for this and need the time integral.


June 11, 2011, 07:28 

#10 
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Glenn Horrocks
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I am sorry, I do not understand your last post. Can you write it again more clearly?


June 12, 2011, 02:03 

#11 
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Andrew
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Calculation of the integral over time is needed for nextmotion 2 products relative to each other in time. We need to count how many times one overlaps another. That is needed some counter. The problem of heat.
If you need a figure for clarity, write to send you 

June 12, 2011, 09:05 

#12 
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Glenn Horrocks
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I still don't know what you are describing. Please post an image.


June 20, 2011, 02:59 

#13 
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Andrew
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In principle, I need to find the time integral of the variable for Ansys not statsianary problem, the picture will not work. Is there a chance?


June 20, 2011, 18:41 

#14 
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Glenn Horrocks
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CFX cannot do time integrals in CEL so it is not easy to do in general.
The reason I am trying to understand what you are doing is often there is another way to implement it, but to suggest something I have to know what you are doing. Can you tell me what variable you are trying to integrate? And what what is the termination condition you want to apply? 

June 23, 2011, 03:30 

#15 
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Andrew
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http://upload.com.ua/get/902689092/1.JPG  shoulder movement
http://upload.com.ua/get/902689101/2.JPG  impact on the blade flow 

June 23, 2011, 07:16 

#16 
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Glenn Horrocks
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I can't seem to view the images on your links. Please put them in the post on the forum, no need for external links.


July 8, 2011, 06:26 

#17 
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Andrew
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sorry, no access to the Internet. You are not hard to explain how it should look like?


July 8, 2011, 07:04 

#18 
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Glenn Horrocks
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Sorry, I did not understand that last post.


July 8, 2011, 08:09 

#19 
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Andrew
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I mean that in what form you would like to see the pictures?


July 10, 2011, 06:44 

#20 
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Glenn Horrocks
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Yes, please put the images on the forum.


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