Function integral over time

GAO · June 8, 2011, 08:15

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.

ghorrocks · June 8, 2011, 09:06

What do you want to take the time integral of?

GAO · June 9, 2011, 04:37

For use as a criterion for stopping the calculation

ghorrocks · June 9, 2011, 07:51

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?

GAO · June 9, 2011, 09:01

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?

ghorrocks · June 9, 2011, 09:13

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?

GAO · June 10, 2011, 07:33

Heat flow, for a problem with the heat flow

ghorrocks · June 10, 2011, 07:44

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.

GAO · June 11, 2011, 04:48

The task is next-passing 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.

ghorrocks · June 11, 2011, 08:28

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

GAO · June 12, 2011, 03:03

Calculation of the integral over time is needed for next-motion 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

ghorrocks · June 12, 2011, 10:05

I still don't know what you are describing. Please post an image.

GAO · June 20, 2011, 03:59

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?

ghorrocks · June 20, 2011, 19:41

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?

GAO · June 23, 2011, 04:30

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

ghorrocks · June 23, 2011, 08:16

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.

GAO · July 8, 2011, 07:26

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

ghorrocks · July 8, 2011, 08:04

Sorry, I did not understand that last post.

GAO · July 8, 2011, 09:09

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

ghorrocks · July 10, 2011, 07:44

Yes, please put the images on the forum.

June 8, 2011, 08:15	Function integral over time	#1
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	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.

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June 8, 2011, 09:06		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	What do you want to take the time integral of?

June 9, 2011, 04:37		#3
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	For use as a criterion for stopping the calculation

June 9, 2011, 07:51		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	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, 09:01		#5
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	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, 09:13		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	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, 07:33		#7
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	Heat flow, for a problem with the heat flow

June 10, 2011, 07:44		#8
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	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, 04:48		#9
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	The task is next-passing 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, 08:28		#10
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	I am sorry, I do not understand your last post. Can you write it again more clearly?

June 12, 2011, 03:03		#11
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	Calculation of the integral over time is needed for next-motion 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, 10:05		#12
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	I still don't know what you are describing. Please post an image.

June 20, 2011, 03:59		#13
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	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, 19:41		#14
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	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, 04:30		#15
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	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, 08:16		#16
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	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, 07:26		#17
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	sorry, no access to the Internet. You are not hard to explain how it should look like?

July 8, 2011, 08:04		#18
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	Sorry, I did not understand that last post.

July 8, 2011, 09:09		#19
GAO New Member Andrew Join Date: Jun 2011 Posts: 13 Rep Power: 15	I mean that in what form you would like to see the pictures?

July 10, 2011, 07:44		#20
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,872 Rep Power: 144	Yes, please put the images on the forum.