Gradient of a variable

October 26, 2005, 05:51

I have variable let us say A which is not solved in the fluent but it is kind of related to UDS C which is solved now I would. I would like to compuet gradients of this variable A over the domain. How can I dod so. I know getting the gradients a variable which is solved for is easy but how to obtain the gradient of A.

P

October 26, 2005, 06:08

You can abuse an UDS as memory if you set the diffusivity to (almost) zero and adjust the flux function so it will return zero. The you can calculate A, store it in the scalar and retrieve the gradient from the scalar. See chapter 5.6.3 of udf guide for an example.

RoM

October 26, 2005, 05:51	Gradient of a variable	#1
P Guest Posts: n/a	I have variable let us say A which is not solved in the fluent but it is kind of related to UDS C which is solved now I would. I would like to compuet gradients of this variable A over the domain. How can I dod so. I know getting the gradients a variable which is solved for is easy but how to obtain the gradient of A. P

October 26, 2005, 06:08	Re: Gradient of a variable	#2
RoM Guest Posts: n/a	You can abuse an UDS as memory if you set the diffusivity to (almost) zero and adjust the flux function so it will return zero. The you can calculate A, store it in the scalar and retrieve the gradient from the scalar. See chapter 5.6.3 of udf guide for an example. RoM

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