******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hi all, Hope you're keeping well. I was trying to understand the working of the Power Kernel in the context of SVV. The input coefficient related to this kernel is to be scaled by *a*h/P* (according to Moura's original paper) where *a* is some measure of local elemental velocity and *h/P* gives local mesh size. So, I ventured into VelocityCorrectionScheme.cpp. Now, 1. I could see where *h/P* is multiplied but not *a *(I imagined that *a* would vary in space but seems like a=1 for the whole domain). Could someone kindly point out where that would be? 2. I noticed that the said scaling takes place just once, in the beginning of the simulation. Is that correct? Thank you in advance. --- *Vishal SAINI*
Hi Vishal, It is indeed only setup at the beginning of each simulation. and by default we assume a = 1. However you can use the SVVDiffCoeff to rescale this to a different value. It should also be possible to provide an average (or any) velocity field to use for this coefficient which reads in the field and determines an average velocity over the element. To try this it looks a if you need to add a Function in the Xml file called SVVVelocityMagnitude (see line 895 of VelocityCorrectionScheme.cpp). Sorry this does not seem to have been documented in the user-guide and needs to be added. Hope that helps. I believe it will use this function for the DGKernel too. Cheers, Spencer. PS I have been working on a new stabilisation based on Gradient Jump Penalisaiton which seems to give better features for lower polynomial orders but this is still a bit experimental. Spencer Sherwin FREng, FRAeS Head of Aerodynamics Section, Director of Research Computing Service, Professor of Computational Fluid Mechanics, Department of Aeronautics, South Kensington Campus, Imperial College London, SW7 2AZ, UK Phone: +44 (0)20 7594 5052 http://www.imperial.ac.uk/people/s.sherwin/ On 14 Jan 2021, at 19:48, Vishal Saini <vishal.saini.nitj@gmail.com<mailto:vishal.saini.nitj@gmail.com>> wrote: This email from vishal.saini.nitj@gmail.com<mailto:vishal.saini.nitj@gmail.com> originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list<https://spam.ic.ac.uk/SpamConsole/Senders.aspx> to disable email stamping for this address. Hi all, Hope you're keeping well. I was trying to understand the working of the Power Kernel in the context of SVV. The input coefficient related to this kernel is to be scaled by a*h/P (according to Moura's original paper) where a is some measure of local elemental velocity and h/P gives local mesh size. So, I ventured into VelocityCorrectionScheme.cpp. Now, 1. I could see where h/P is multiplied but not a (I imagined that a would vary in space but seems like a=1 for the whole domain). Could someone kindly point out where that would be? 2. I noticed that the said scaling takes place just once, in the beginning of the simulation. Is that correct? Thank you in advance. --- Vishal SAINI _______________________________________________ Nektar-users mailing list Nektar-users@imperial.ac.uk<mailto:Nektar-users@imperial.ac.uk> https://mailman.ic.ac.uk/mailman/listinfo/nektar-users
participants (2)
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Sherwin, Spencer J
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Vishal Saini