画"销自割姐回到"川川口创刁升叫
Hui
第
41
卷第
5
期
2010
年
10
月
中南大学学报(自然科学版)
Journal
of
Central
South
University (Science
and
Technology)
Vo
l.
41
No
.5
Oc
t.
2010
基于非结构化网格的三维大地电磁自适应矢量有限元模拟
刘长生
1
,
2
,汤井田任政勇
1
,
3
,冯德山
l
(1.中南大学信息物理工程学院,湖南长沙,
410083;
2.
长沙航空职业技术学院计算机系,湖南长沙,
410014;
3.
瑞士联邦理工学院
(EIH)
地球物理系,瑞士苏黎士,
CH8092)
摘
要:基于能够模拟复杂模型的非结构化网格,提出基于矢量单元的二维白适应有限元大地电磁模拟算法。其
过程是:利用残差型的后验误差算子初步估算粗网格上的单元误差,通过力
11
密误差超过限定的单元,生成新的网
格:对新的网格重复上一步过程,从而得到更加精确的数值结果:重复迭代过程直到计算结果的精度达到预定要
求为止,从而生成最优化的有限元网格:基于
COMMEMI
3D-1
MT
模型的数值模拟,验证本文算法的正确性。
研究结果表明:通过自适应的网格加密和迭代求解过程,本文算法可以产生迭代收敛的数值结果,计算结果具有
较高的精度。
关键词
MT
三维正演;非结构化网格;矢量有限元;残差型后验误差
h-
型自适应有限元
中图分类号
P631.322
文献标志码
A
文章编号
1672
一
7207(2010)05-1855-05
Three-dimension magnetotellurics modeling
by
adaptive edge
finite-element using
unstructured
meshes
LIU
Chang-sheng
1
,2,
TANG
Jing-tian
1
,
REN
Zheng-yong
1
,3,
FENG
De-shan
1
(1.
School o
fI
nfo-physics and Geometrics Engineering, Central South University, Changsha 410083, China;
2.
Department
of
Computer
Sci
巳
nce
,
Changsha Aeronautical Vocational and Technical
Co
l1
eg
巳,
Changsha
410014, China;
3.
Institute
of
Geophysics, ETH-Swiss Federal Institute ofTechnology, Zurich CH8092, Switzerland)
Abstract:
Based on unstructured grid which can simulate complex geoelectric models, the vector edge-based
fini
饨
-elements
were proposed. An adaptive finite element three-dimensional magnetotelluric modeling algorithm was
introduced.
Th
巳
procedures
are
as
fo
l1
ows: Element errors was estimated by a residual-based posteriori error on the coarse
grid
, and then elements with high error indicators were refined
to
generate a new grid. A new finite-element numerical
processes were repeated on this new mesh to obtain more accurate and reliable numerical results. The iterative process
was terminated until the accuracy ofresults on the final mesh became a required one. The COMMEMI
3D-l
model was
tested to
veri
fY
the correctness
of
the algorithm. The results show that for a complex three-dimensional electromagnetic
model
of
the earth, using the adaptive mesh refinement and iterative solution
procedur
巳,
the algorithm can generate
iterative numerical results with high reliability.
Key words: magnetotelluric three-dimensional modeling; unstructured mesh; vector finite element method; residual
based error estimation; h-adaptive finite element method
自
Coggon[l]
提出地球物理电磁中的有限单元算
法
(Finite
element
method
,
FEM)
以来,
FEM
开始在电磁
勘探领域得到广泛应用
[2
一匀。
Badea
等
[6]
利用节点型的
线性有限单元模拟了可控源音频大地电磁法;
Mitsuhata
收稿日期
2010-03-31
;修回日期
20