average planes in a quasi 3-D simulation
******************* 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. ******************* Dear All, How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation? Kind regards syavash
Hi Syavash, Are you referring to averaging across the homogeneous (z-th) direction? i.e the Fourier 0-th mode. If so, you can use FieldConvert -m meanmode. Hope this helps Cheers Chi Hin Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: nektar-users-bounces@imperial.ac.uk <nektar-users-bounces@imperial.ac.uk> on behalf of Ehsan Asgari <eh.asgari@gmail.com> Sent: Thursday, August 31, 2023 8:35:19 AM To: nektar-users <nektar-users@imperial.ac.uk> Subject: [Nektar-users] average planes in a quasi 3-D simulation This email from eh.asgari@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. Dear All, How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation? Kind regards syavash
Hi Chi Hin Thanks for your reply. Yes I meant the spanwise averaging. But I guess this method would give a 2-D expansion containing the mean mode of instantaneous quantities. What can I do if I'd also want to spanwise-average quantities such as Reynolds stresses? Kind regards syavash On Thu, Aug 31, 2023 at 11:37 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk> wrote:
Hi Syavash,
Are you referring to averaging across the homogeneous (z-th) direction? i.e the Fourier 0-th mode.
If so, you can use FieldConvert -m meanmode. Hope this helps
Cheers Chi Hin
Get Outlook for iOS <https://aka.ms/o0ukef> ------------------------------ *From:* nektar-users-bounces@imperial.ac.uk < nektar-users-bounces@imperial.ac.uk> on behalf of Ehsan Asgari < eh.asgari@gmail.com> *Sent:* Thursday, August 31, 2023 8:35:19 AM *To:* nektar-users <nektar-users@imperial.ac.uk> *Subject:* [Nektar-users] average planes in a quasi 3-D simulation
This email from eh.asgari@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.
Dear All,
How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation?
Kind regards syavash
Hi Syavash, Yes, you are right. There's a ReynoldsStresses (RS) filter that computes the time-averaged RS. You could apply FieldConvert -m meanmode on the output .fld from the filter. Unfortunately, this process computes the spanwise- & time-averaged RS. I'm not entirely sure how to compute the spanwise-averaged, instantaneous RS if that's your goal. Perhaps I could suggest tinkering with FieldConvert -m fieldfromstring (user guide v5.2) to create an instantaneous RS field manually. Hope this helps. Cheers, Chi Hin ________________________________ From: Ehsan Asgari <eh.asgari@gmail.com> Sent: 31 August 2023 09:42 To: Chan, Chi Hin <chi.chan19@imperial.ac.uk> Cc: nektar-users <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] average planes in a quasi 3-D simulation Hi Chi Hin Thanks for your reply. Yes I meant the spanwise averaging. But I guess this method would give a 2-D expansion containing the mean mode of instantaneous quantities. What can I do if I'd also want to spanwise-average quantities such as Reynolds stresses? Kind regards syavash On Thu, Aug 31, 2023 at 11:37 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk<mailto:chi.chan19@imperial.ac.uk>> wrote: Hi Syavash, Are you referring to averaging across the homogeneous (z-th) direction? i.e the Fourier 0-th mode. If so, you can use FieldConvert -m meanmode. Hope this helps Cheers Chi Hin Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: nektar-users-bounces@imperial.ac.uk<mailto:nektar-users-bounces@imperial.ac.uk> <nektar-users-bounces@imperial.ac.uk<mailto:nektar-users-bounces@imperial.ac.uk>> on behalf of Ehsan Asgari <eh.asgari@gmail.com<mailto:eh.asgari@gmail.com>> Sent: Thursday, August 31, 2023 8:35:19 AM To: nektar-users <nektar-users@imperial.ac.uk<mailto:nektar-users@imperial.ac.uk>> Subject: [Nektar-users] average planes in a quasi 3-D simulation This email from eh.asgari@gmail.com<mailto:eh.asgari@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. Dear All, How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation? Kind regards syavash
Thanks Chi Hin. This is very helpful. Actually I needed spanwise- & time-averaged RS as you indicated. In fact, I was not sure if the meanmode filter would work on an average field (RS or mean velocity). A new issue is that I see footprints of macro-elements on the averaged RS, while the averaged velocity is conveniently smooth. Perhaps I should extend the averaging time to alleviate this effect. Do you have any suggestions? Kind regards syavash On Fri, Sep 1, 2023 at 1:13 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk> wrote:
Hi Syavash,
Yes, you are right.
There's a ReynoldsStresses (RS) filter that computes the time-averaged RS. You could apply FieldConvert -m meanmode on the output .fld from the filter.
Unfortunately, this process computes the spanwise- & time-averaged RS. I'm not entirely sure how to compute the spanwise-averaged, instantaneous RS if that's your goal. Perhaps I could suggest tinkering with FieldConvert -m fieldfromstring (user guide v5.2) to create an instantaneous RS field manually.
Hope this helps.
Cheers, Chi Hin ------------------------------ *From:* Ehsan Asgari <eh.asgari@gmail.com> *Sent:* 31 August 2023 09:42 *To:* Chan, Chi Hin <chi.chan19@imperial.ac.uk> *Cc:* nektar-users <nektar-users@imperial.ac.uk> *Subject:* Re: [Nektar-users] average planes in a quasi 3-D simulation
Hi Chi Hin
Thanks for your reply. Yes I meant the spanwise averaging. But I guess this method would give a 2-D expansion containing the mean mode of instantaneous quantities. What can I do if I'd also want to spanwise-average quantities such as Reynolds stresses?
Kind regards syavash
On Thu, Aug 31, 2023 at 11:37 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk> wrote:
Hi Syavash,
Are you referring to averaging across the homogeneous (z-th) direction? i.e the Fourier 0-th mode.
If so, you can use FieldConvert -m meanmode. Hope this helps
Cheers Chi Hin
Get Outlook for iOS <https://aka.ms/o0ukef> ------------------------------ *From:* nektar-users-bounces@imperial.ac.uk < nektar-users-bounces@imperial.ac.uk> on behalf of Ehsan Asgari < eh.asgari@gmail.com> *Sent:* Thursday, August 31, 2023 8:35:19 AM *To:* nektar-users <nektar-users@imperial.ac.uk> *Subject:* [Nektar-users] average planes in a quasi 3-D simulation
This email from eh.asgari@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.
Dear All,
How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation?
Kind regards syavash
Hi Syavash, Great, meanmode module would work on an averaged field. If I were to understand the issue of “macro-elements on average RS” correctly, you are observing the footprint of the element edges on your RS field/plots. I’ve experienced similar issues before, and it fixed it by increasing spatial resolution. You might want to try increasing spatial resolution or extend time averaging. Good luck! Cheers Chi Hin Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: Ehsan Asgari <eh.asgari@gmail.com> Sent: Friday, September 1, 2023 8:33:13 AM To: Chan, Chi Hin <chi.chan19@imperial.ac.uk> Cc: nektar-users <nektar-users@imperial.ac.uk> Subject: Re: [Nektar-users] average planes in a quasi 3-D simulation Thanks Chi Hin. This is very helpful. Actually I needed spanwise- & time-averaged RS as you indicated. In fact, I was not sure if the meanmode filter would work on an average field (RS or mean velocity). A new issue is that I see footprints of macro-elements on the averaged RS, while the averaged velocity is conveniently smooth. Perhaps I should extend the averaging time to alleviate this effect. Do you have any suggestions? Kind regards syavash On Fri, Sep 1, 2023 at 1:13 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk<mailto:chi.chan19@imperial.ac.uk>> wrote: Hi Syavash, Yes, you are right. There's a ReynoldsStresses (RS) filter that computes the time-averaged RS. You could apply FieldConvert -m meanmode on the output .fld from the filter. Unfortunately, this process computes the spanwise- & time-averaged RS. I'm not entirely sure how to compute the spanwise-averaged, instantaneous RS if that's your goal. Perhaps I could suggest tinkering with FieldConvert -m fieldfromstring (user guide v5.2) to create an instantaneous RS field manually. Hope this helps. Cheers, Chi Hin ________________________________ From: Ehsan Asgari <eh.asgari@gmail.com<mailto:eh.asgari@gmail.com>> Sent: 31 August 2023 09:42 To: Chan, Chi Hin <chi.chan19@imperial.ac.uk<mailto:chi.chan19@imperial.ac.uk>> Cc: nektar-users <nektar-users@imperial.ac.uk<mailto:nektar-users@imperial.ac.uk>> Subject: Re: [Nektar-users] average planes in a quasi 3-D simulation Hi Chi Hin Thanks for your reply. Yes I meant the spanwise averaging. But I guess this method would give a 2-D expansion containing the mean mode of instantaneous quantities. What can I do if I'd also want to spanwise-average quantities such as Reynolds stresses? Kind regards syavash On Thu, Aug 31, 2023 at 11:37 AM Chan, Chi Hin <chi.chan19@imperial.ac.uk<mailto:chi.chan19@imperial.ac.uk>> wrote: Hi Syavash, Are you referring to averaging across the homogeneous (z-th) direction? i.e the Fourier 0-th mode. If so, you can use FieldConvert -m meanmode. Hope this helps Cheers Chi Hin Get Outlook for iOS<https://aka.ms/o0ukef> ________________________________ From: nektar-users-bounces@imperial.ac.uk<mailto:nektar-users-bounces@imperial.ac.uk> <nektar-users-bounces@imperial.ac.uk<mailto:nektar-users-bounces@imperial.ac.uk>> on behalf of Ehsan Asgari <eh.asgari@gmail.com<mailto:eh.asgari@gmail.com>> Sent: Thursday, August 31, 2023 8:35:19 AM To: nektar-users <nektar-users@imperial.ac.uk<mailto:nektar-users@imperial.ac.uk>> Subject: [Nektar-users] average planes in a quasi 3-D simulation This email from eh.asgari@gmail.com<mailto:eh.asgari@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. Dear All, How can I average the solutions of planes across the homogenous direction in a Quasi 3-D simulation? Kind regards syavash
participants (2)
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Chan, Chi Hin
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Ehsan Asgari