You can subscribe to this list here.
2003 
_{Jan}

_{Feb}

_{Mar}

_{Apr}

_{May}

_{Jun}

_{Jul}

_{Aug}

_{Sep}
(2) 
_{Oct}
(2) 
_{Nov}
(27) 
_{Dec}
(31) 

2004 
_{Jan}
(6) 
_{Feb}
(15) 
_{Mar}
(33) 
_{Apr}
(10) 
_{May}
(46) 
_{Jun}
(11) 
_{Jul}
(21) 
_{Aug}
(15) 
_{Sep}
(13) 
_{Oct}
(23) 
_{Nov}
(1) 
_{Dec}
(8) 
2005 
_{Jan}
(27) 
_{Feb}
(57) 
_{Mar}
(86) 
_{Apr}
(23) 
_{May}
(37) 
_{Jun}
(34) 
_{Jul}
(24) 
_{Aug}
(17) 
_{Sep}
(50) 
_{Oct}
(24) 
_{Nov}
(10) 
_{Dec}
(60) 
2006 
_{Jan}
(47) 
_{Feb}
(46) 
_{Mar}
(127) 
_{Apr}
(19) 
_{May}
(26) 
_{Jun}
(62) 
_{Jul}
(47) 
_{Aug}
(51) 
_{Sep}
(61) 
_{Oct}
(42) 
_{Nov}
(50) 
_{Dec}
(33) 
2007 
_{Jan}
(60) 
_{Feb}
(55) 
_{Mar}
(77) 
_{Apr}
(102) 
_{May}
(82) 
_{Jun}
(102) 
_{Jul}
(169) 
_{Aug}
(117) 
_{Sep}
(80) 
_{Oct}
(37) 
_{Nov}
(51) 
_{Dec}
(43) 
2008 
_{Jan}
(71) 
_{Feb}
(94) 
_{Mar}
(98) 
_{Apr}
(125) 
_{May}
(54) 
_{Jun}
(119) 
_{Jul}
(60) 
_{Aug}
(111) 
_{Sep}
(118) 
_{Oct}
(125) 
_{Nov}
(119) 
_{Dec}
(94) 
2009 
_{Jan}
(109) 
_{Feb}
(38) 
_{Mar}
(93) 
_{Apr}
(88) 
_{May}
(29) 
_{Jun}
(57) 
_{Jul}
(53) 
_{Aug}
(48) 
_{Sep}
(68) 
_{Oct}
(151) 
_{Nov}
(23) 
_{Dec}
(35) 
2010 
_{Jan}
(84) 
_{Feb}
(60) 
_{Mar}
(184) 
_{Apr}
(112) 
_{May}
(60) 
_{Jun}
(90) 
_{Jul}
(23) 
_{Aug}
(70) 
_{Sep}
(119) 
_{Oct}
(27) 
_{Nov}
(47) 
_{Dec}
(54) 
2011 
_{Jan}
(22) 
_{Feb}
(19) 
_{Mar}
(92) 
_{Apr}
(93) 
_{May}
(35) 
_{Jun}
(91) 
_{Jul}
(32) 
_{Aug}
(61) 
_{Sep}
(7) 
_{Oct}
(69) 
_{Nov}
(81) 
_{Dec}
(23) 
2012 
_{Jan}
(64) 
_{Feb}
(95) 
_{Mar}
(35) 
_{Apr}
(36) 
_{May}
(63) 
_{Jun}
(98) 
_{Jul}
(70) 
_{Aug}
(171) 
_{Sep}
(149) 
_{Oct}
(64) 
_{Nov}
(67) 
_{Dec}
(126) 
2013 
_{Jan}
(108) 
_{Feb}
(104) 
_{Mar}
(171) 
_{Apr}
(133) 
_{May}
(108) 
_{Jun}
(100) 
_{Jul}
(93) 
_{Aug}
(126) 
_{Sep}
(74) 
_{Oct}
(59) 
_{Nov}
(145) 
_{Dec}
(93) 
2014 
_{Jan}
(38) 
_{Feb}
(45) 
_{Mar}
(26) 
_{Apr}
(41) 
_{May}
(125) 
_{Jun}
(70) 
_{Jul}
(61) 
_{Aug}
(66) 
_{Sep}
(60) 
_{Oct}
(110) 
_{Nov}
(27) 
_{Dec}
(30) 
2015 
_{Jan}
(43) 
_{Feb}
(67) 
_{Mar}
(71) 
_{Apr}
(92) 
_{May}
(39) 
_{Jun}
(15) 
_{Jul}
(46) 
_{Aug}
(63) 
_{Sep}
(84) 
_{Oct}
(82) 
_{Nov}
(69) 
_{Dec}
(45) 
2016 
_{Jan}
(92) 
_{Feb}
(91) 
_{Mar}
(148) 
_{Apr}
(43) 
_{May}
(58) 
_{Jun}
(117) 
_{Jul}
(92) 
_{Aug}
(140) 
_{Sep}
(49) 
_{Oct}
(33) 
_{Nov}
(85) 
_{Dec}
(40) 
2017 
_{Jan}
(41) 
_{Feb}
(36) 
_{Mar}
(49) 
_{Apr}
(41) 
_{May}
(68) 
_{Jun}

_{Jul}

_{Aug}

_{Sep}

_{Oct}

_{Nov}

_{Dec}

S  M  T  W  T  F  S 



1
(2) 
2
(3) 
3
(1) 
4

5
(2) 
6
(1) 
7
(1) 
8
(1) 
9

10

11
(1) 
12

13

14
(3) 
15
(2) 
16

17

18
(5) 
19
(2) 
20

21
(1) 
22
(7) 
23
(1) 
24
(21) 
25
(4) 
26

27
(2) 
28

29
(4) 
30
(4) 
31
(3) 


From: John Peterson <peterson@cf...>  20080122 23:14:17

David Knezevic writes: > I'd like to implement the following boundary condition for the outflow > of a channel: > du/dn  n*p = 0, > where n is the outward normal and p is the pressure. It seems to me that > this BC would result in an extra boundary term $\int_{\partial\Omega} n > p \ds$ being added to the momentum equations? Isn't this the natural boundary condition, assuming you integrated by parts on the pressure term? In that case I don't think you get any extra terms. J > In my case the outward normal on the outflow boundary is n = (1,0). I > tried to implement this BC using the following code in side_constraint: > > if (boundary_id == outflow_id) > Fu(i) = JxW_side[qp] * p * phi_side[i][qp]; > > if (boundary_id != outflow_id) > Fv(i) += JxW_side[qp] * penalty * > (v  v_value) * phi_side[i][qp]; > > if (boundary_id != outflow_id) > Kuu(i,j) += JxW_side[qp] * penalty * > phi_side[i][qp] * phi_side[j][qp]; > if (boundary_id != outflow_id) > Kvv(i,j) += JxW_side[qp] * penalty * > phi_side[i][qp] * phi_side[j][qp]; > > where p = side_value(p_var, qp), plus there are other BCs not shown > here for inflow and noslip. This doesn't appear to work; the Newton > convergence fails with these BCs. If anyone can point out how to > properly implement this BC, I'd be most appreciative :) > > Cheers, > David 
From: Roy Stogner <roystgnr@ic...>  20080122 23:02:58

On Tue, 22 Jan 2008, David Knezevic wrote: > I'd like to implement the following boundary condition for the outflow > of a channel: > du/dn  n*p = 0, > where n is the outward normal and p is the pressure. It seems to me that > this BC would result in an extra boundary term $\int_{\partial\Omega} n > p \ds$ being added to the momentum equations? That seems right. > In my case the outward normal on the outflow boundary is n = (1,0). I > tried to implement this BC using the following code in side_constraint: > > if (boundary_id == outflow_id) > Fu(i) = JxW_side[qp] * p * phi_side[i][qp]; > > if (boundary_id != outflow_id) > Fv(i) += JxW_side[qp] * penalty * > (v  v_value) * phi_side[i][qp]; > > if (boundary_id != outflow_id) > Kuu(i,j) += JxW_side[qp] * penalty * > phi_side[i][qp] * phi_side[j][qp]; > if (boundary_id != outflow_id) > Kvv(i,j) += JxW_side[qp] * penalty * > phi_side[i][qp] * phi_side[j][qp]; > > where p = side_value(p_var, qp), plus there are other BCs not shown > here for inflow and noslip. This doesn't appear to work; the Newton > convergence fails with these BCs. If anyone can point out how to > properly implement this BC, I'd be most appreciative :) For the new Fu term, you'll need a corresponding Jacobian term. Try: if (boundary_id == outflow_id) Kup(i,j) = JxW_side[qp] * psi_side[j][qp] * phi_side[i][qp];  Roy 
From: David Knezevic <dave.knez@gm...>  20080122 23:02:16

> It seems to me that this BC would result in an extra boundary term $\int_{\partial\Omega} n > p \ds$ being added to the momentum equations? > oops, I meant $\int_{\partial\Omega} n p \phi \ds$  David 
From: David Knezevic <david.knezevic@ba...>  20080122 22:53:32

I'd like to implement the following boundary condition for the outflow of a channel: du/dn  n*p = 0, where n is the outward normal and p is the pressure. It seems to me that this BC would result in an extra boundary term $\int_{\partial\Omega} n p \ds$ being added to the momentum equations? In my case the outward normal on the outflow boundary is n = (1,0). I tried to implement this BC using the following code in side_constraint: if (boundary_id == outflow_id) Fu(i) = JxW_side[qp] * p * phi_side[i][qp]; if (boundary_id != outflow_id) Fv(i) += JxW_side[qp] * penalty * (v  v_value) * phi_side[i][qp]; if (boundary_id != outflow_id) Kuu(i,j) += JxW_side[qp] * penalty * phi_side[i][qp] * phi_side[j][qp]; if (boundary_id != outflow_id) Kvv(i,j) += JxW_side[qp] * penalty * phi_side[i][qp] * phi_side[j][qp]; where p = side_value(p_var, qp), plus there are other BCs not shown here for inflow and noslip. This doesn't appear to work; the Newton convergence fails with these BCs. If anyone can point out how to properly implement this BC, I'd be most appreciative :) Cheers, David 
From: John Peterson <peterson@cf...>  20080122 22:20:50

Speak of the devil. I will try to attend this talk next month, though it looks like it will focus on more exotic FE spaces... J Sue Hennigar writes: > ICES SEMINAR > > Prof. Nilima Nigam > Department of Mathematics and Statistics > McGill University > "Highorder Conforming Finite Elements for a Pyramid" > > Abstract: > Pyramidal elements can arise in hybrid meshes as "gluing" elements > between hexahedral and tetrahedral structures. A longoutstanding > problem has been how to design highorder conforming finite elements on > the pyramid, which are compatible on their faces and edges with existing > elements from neighbouring tetrahedra or hexahedra. In this joint with > Joel Phillips, we present highorder elements, which satisfy the exact > sequence property for H1, H(curl), H(div) and L2, and which also have > the required compatibility features. Projectionbased interpolation > provides a natural strategy for the > construction, and also allows for a commuting diagram property. Along > the way, we describe the (surprising) result that such finite elements > cannot comprise of polynomial functions alone. > > February 7, 2008 > 3:30  5:00 pm > ACES 6.304 
From: John Peterson <peterson@cf...>  20080122 20:02:46

Michael Povolotskyi writes: > Dear Libmesh developers, at some point it appears such a comment in > the code (see below). Does it mean that the results obtained on a > mesh that contains pyramids may be wrong? Or they are for sure wrong? Hi, I was the one to add that comment. I didn't investigate the issue further, unfortunately. You can try it out yourself with a pyramid of known volume... Either the geometric volume formula we have is wrong or there is a problem with the quadrature rule or basis functions. If you take a look at the pyramid's basis functions, you will notice they are rational functions, not polynomials. John 
From: Michael Povolotskyi <povolotskyi@in...>  20080122 19:08:26

<!DOCTYPE html PUBLIC "//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> </head> <body bgcolor="#ffffff" text="#000000"> <pre class="fragment">Dear Libmesh developers, at some point it appears such a comment in the code (see below). Does it mean that the results obtained on a mesh that contains pyramids may be wrong? Or they are for sure wrong? Thank you, Michael. <a class="code" href="http://libmesh.sourceforge.net/doxygen/libmesh__common_8h.php#cd9440203db8e3b36d61f62fe6567258">Real</a>; <a class="code" href="http://libmesh.sourceforge.net/doxygen/classPyramid5.php#c92644b060057bd04f860055ba2c7014">Pyramid5::volume</a>; ()<span class="keyword"> const</span> <span class="comment"></span> 00266 <span class="comment">// Note: the volume returned by summing the Jacobian times the</span> 00267 <span class="comment">// quadrature weights over all the quadrature points for the</span> 00268 <span class="comment">// pyramid element does *not* give the correct volume (the formula</span> 00269 <span class="comment">// in this function gives the correct volume). This implies there</span> 00270 <span class="comment">// is something wrong with the firstorder Lagrange shape functions</span> 00271 <span class="comment">// or the quadrature rules for the Pyramid5.</span></pre> <pre class="mozsignature" cols="72"> </pre> </body> </html> 