Re: help! bilinear basis function conver - 未名空间MITBBS历史存档

国际科技财经博客移民网络热点娱乐民生时事公众号

Redian新闻

>未名空间

>Computation - 科学计算

Re: help! bilinear basis function conver

Re: help! bilinear basis function conver# Computation - 科学计算

x*y2003-12-19 08:12

1 楼

Now I'm also wondering about this.
I got my results that bilinear basis function (quadrilateral element in 2-D)
yields 1.89 convergence rate for conformation tensor (or elastic stress) and
linear basis function (tetrahedral element in 3-D) yields 1.65 convergence
rate for conformation tensor. I use DEVSS-SUPG method for viscoelastic flow
confpuation. A reference paper shows that DEVSS-SUPG method yields r+0.5 which
is 1.5 in my case. But I think 1.89 is far above 1.5, and my advisor thinks
bilin

w*d2003-12-19 08:12

2 楼

No idea why bilinear is better than linear.
Long time ago, by using an unusual strategy,
we obtained a O(h^2) rectangular element
with 12 degree of freedom. The error is a little bigger than that from
bi-quadratic basis. But the order is the same.
I know nothing about superconvergence.
The high convergence rate might be due to some special property of
the conformation tensor or even your mesh.
BTW, i applied for the postdoc position at Rice. Not sure if i can get it.

【在 x*y 的大作中提到】

: Now I'm also wondering about this.
: I got my results that bilinear basis function (quadrilateral element in 2-D)
: yields 1.89 convergence rate for conformation tensor (or elastic stress) and
: linear basis function (tetrahedral element in 3-D) yields 1.65 convergence
: rate for conformation tensor. I use DEVSS-SUPG method for viscoelastic flow
: confpuation. A reference paper shows that DEVSS-SUPG method yields r+0.5 which
: is 1.5 in my case. But I think 1.89 is far above 1.5, and my advisor thinks
: bilin

x*y2003-12-19 08:12

3 楼

Ah, which professor do you apply for? and in which department? I might be able
to provide some informations to you.
Thank you for your infos about convergence rate. It's helpful to me when I
gather theories and references to explain my reults.

2-D)
and
flow
which
thinks

【在 w**d 的大作中提到】

: No idea why bilinear is better than linear.
: Long time ago, by using an unusual strategy,
: we obtained a O(h^2) rectangular element
: with 12 degree of freedom. The error is a little bigger than that from
: bi-quadratic basis. But the order is the same.
: I know nothing about superconvergence.
: The high convergence rate might be due to some special property of
: the conformation tensor or even your mesh.
: BTW, i applied for the postdoc position at Rice. Not sure if i can get it.