## Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh

 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Derek Gaston - 2013-04-23 20:34:02 ```lol - whoops - disregard that email... wrong one ;-) On Tue, Apr 23, 2013 at 2:05 PM, John Peterson wrote: > On Tue, Apr 23, 2013 at 2:04 PM, Derek Gaston wrote: > > Ling - come talk to David and or John about it if it's still not clear. > > ??? > > -- > John > ```

 [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Zhang - 2013-04-23 02:41:48 ``` Dear all, As a beginner of libMesh, I am using it to build an incompressible N-S solver with projection method. When I am trying to calculate as follows, u^{n+1}=u^{n}-dt*grad(p), I wonder how to project the pressure gradient grad(p) in Q1 space into the velocity u 's space Q2. Is there any built-in function for such a task? Thanks Zhenyu Zhang ```
 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Kirk, Benjamin (JSC-EG311) - 2013-04-23 15:26:32 ```Are you using a finite element method? If so, you wind up weighting this term under an integral and everything works out. -Ben On Apr 22, 2013, at 7:42 PM, "Zhang" wrote: > > > > Dear all, > > As a beginner of libMesh, I am using it to build an incompressible N-S solver with projection method. > > When I am trying to calculate as follows, > > u^{n+1}=u^{n}-dt*grad(p), > > > I wonder how to project the pressure gradient grad(p) in Q1 space into the velocity u 's space Q2. Is there > any built-in function for such a task? > > > > Thanks > > Zhenyu Zhang > > > > > > > ------------------------------------------------------------------------------ > Precog is a next-generation analytics platform capable of advanced > analytics on semi-structured data. The platform includes APIs for building > apps and a phenomenal toolset for data science. Developers can use > our toolset for easy data analysis & visualization. Get a free account! > http://www2.precog.com/precogplatform/slashdotnewsletter > _______________________________________________ > Libmesh-users mailing list > Libmesh-users@... > https://lists.sourceforge.net/lists/listinfo/libmesh-users ```
 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Kirk, Benjamin (JSC-EG311) - 2013-04-23 15:29:57 ```And by that I mean you get a mass matrix on the left hand side and the pressure gradient only shows up inside the source term, where it is integrated inside he element and is well posed. -Ben On Apr 23, 2013, at 8:26 AM, "Kirk, Benjamin (JSC-EG311)" wrote: > Are you using a finite element method? If so, you wind up weighting this term under an integral and everything works out. > > -Ben > > > On Apr 22, 2013, at 7:42 PM, "Zhang" wrote: > >> >> >> >> Dear all, >> >> As a beginner of libMesh, I am using it to build an incompressible N-S solver with projection method. >> >> When I am trying to calculate as follows, >> >> u^{n+1}=u^{n}-dt*grad(p), >> >> >> I wonder how to project the pressure gradient grad(p) in Q1 space into the velocity u 's space Q2. Is there >> any built-in function for such a task? >> >> >> >> Thanks >> >> Zhenyu Zhang >> >> >> >> >> >> >> ------------------------------------------------------------------------------ >> Precog is a next-generation analytics platform capable of advanced >> analytics on semi-structured data. The platform includes APIs for building >> apps and a phenomenal toolset for data science. Developers can use >> our toolset for easy data analysis & visualization. Get a free account! >> http://www2.precog.com/precogplatform/slashdotnewsletter >> _______________________________________________ >> Libmesh-users mailing list >> Libmesh-users@... >> https://lists.sourceforge.net/lists/listinfo/libmesh-users > > ------------------------------------------------------------------------------ > Try New Relic Now & We'll Send You this Cool Shirt > New Relic is the only SaaS-based application performance monitoring service > that delivers powerful full stack analytics. Optimize and monitor your > browser, app, & servers with just a few lines of code. Try New Relic > and get this awesome Nerd Life shirt! http://p.sf.net/sfu/newrelic_d2d_apr > _______________________________________________ > Libmesh-users mailing list > Libmesh-users@... > https://lists.sourceforge.net/lists/listinfo/libmesh-users ```
 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Derek Gaston - 2013-04-23 20:04:59 ```Ling - come talk to David and or John about it if it's still not clear. Derek On Tue, Apr 23, 2013 at 9:29 AM, Kirk, Benjamin (JSC-EG311) < benjamin.kirk-1@...> wrote: > And by that I mean you get a mass matrix on the left hand side and the > pressure gradient only shows up inside the source term, where it is > integrated inside he element and is well posed. > > -Ben > > > On Apr 23, 2013, at 8:26 AM, "Kirk, Benjamin (JSC-EG311)" < > benjamin.kirk-1@...> wrote: > > > Are you using a finite element method? If so, you wind up weighting this > term under an integral and everything works out. > > > > -Ben > > > > > > On Apr 22, 2013, at 7:42 PM, "Zhang" wrote: > > > >> > >> > >> > >> Dear all, > >> > >> As a beginner of libMesh, I am using it to build an incompressible N-S > solver with projection method. > >> > >> When I am trying to calculate as follows, > >> > >> u^{n+1}=u^{n}-dt*grad(p), > >> > >> > >> I wonder how to project the pressure gradient grad(p) in Q1 space into > the velocity u 's space Q2. Is there > >> any built-in function for such a task? > >> > >> > >> > >> Thanks > >> > >> Zhenyu Zhang > >> > >> > >> > >> > >> > >> > >> > ------------------------------------------------------------------------------ > >> Precog is a next-generation analytics platform capable of advanced > >> analytics on semi-structured data. The platform includes APIs for > building > >> apps and a phenomenal toolset for data science. Developers can use > >> our toolset for easy data analysis & visualization. Get a free account! > >> http://www2.precog.com/precogplatform/slashdotnewsletter > >> _______________________________________________ > >> Libmesh-users mailing list > >> Libmesh-users@... > >> https://lists.sourceforge.net/lists/listinfo/libmesh-users > > > > > ------------------------------------------------------------------------------ > > Try New Relic Now & We'll Send You this Cool Shirt > > New Relic is the only SaaS-based application performance monitoring > service > > that delivers powerful full stack analytics. Optimize and monitor your > > browser, app, & servers with just a few lines of code. Try New Relic > > and get this awesome Nerd Life shirt! > http://p.sf.net/sfu/newrelic_d2d_apr > > _______________________________________________ > > Libmesh-users mailing list > > Libmesh-users@... > > https://lists.sourceforge.net/lists/listinfo/libmesh-users > > > ------------------------------------------------------------------------------ > Try New Relic Now & We'll Send You this Cool Shirt > New Relic is the only SaaS-based application performance monitoring service > that delivers powerful full stack analytics. Optimize and monitor your > browser, app, & servers with just a few lines of code. Try New Relic > and get this awesome Nerd Life shirt! http://p.sf.net/sfu/newrelic_d2d_apr > _______________________________________________ > Libmesh-users mailing list > Libmesh-users@... > https://lists.sourceforge.net/lists/listinfo/libmesh-users > ```
 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: John Peterson - 2013-04-23 20:06:13 ```On Tue, Apr 23, 2013 at 2:04 PM, Derek Gaston wrote: > Ling - come talk to David and or John about it if it's still not clear. ??? -- John ```
 Re: [Libmesh-users] How to project a solution from Q1 to Q2 space using libmesh From: Derek Gaston - 2013-04-23 20:34:02 ```lol - whoops - disregard that email... wrong one ;-) On Tue, Apr 23, 2013 at 2:05 PM, John Peterson wrote: > On Tue, Apr 23, 2013 at 2:04 PM, Derek Gaston wrote: > > Ling - come talk to David and or John about it if it's still not clear. > > ??? > > -- > John > ```