Services & Resources / Wolfram Forums
-----
 /
MathGroup Archive
1999
*January
*February
*March
*April
*May
*June
*July
*August
*September
*October
*November
*December
*Archive Index
*Ask about this page
*Print this page
*Give us feedback
*Sign up for the Wolfram Insider

MathGroup Archive 1999

[Date Index] [Thread Index] [Author Index]

Search the Archive

Composing a stiffness matrix

  • To: mathgroup at smc.vnet.net
  • Subject: [mg20328] Composing a stiffness matrix
  • From: "Toshiyuki (Toshi) Meshii" <meshii at mech.fukui-u.ac.jp>
  • Date: Fri, 15 Oct 1999 20:20:51 -0400
  • Sender: owner-wri-mathgroup at wolfram.com

Hi,

I am wondering whether we can use Mathematica to systematically compose a
stiffness matrix in Finite Element Method.
Please give me an advice on this problem.

An example problem is as follows:
I know
   Eq (1)   {f1,f2}={{ka,-ka},{-ka,ka}}・瘢雹{u1,u2}
   Eq (2)   {f2,f3}={{kb,-kb},{-kb,kb}}・瘢雹{u2,u3}
and want to construct Eq (3) from these two equations systematically.
   Eq (3)   {f1,f 2,f3}=K・瘢雹{u1,u2,u3}
Here, matrix K is called a stiffness matrix and it's elements are
 K={{ka,-ka,0},{-ka,ka+kb,-kb},{0,-Kb,Kb}}
How can we construct matrix K in Eq  (3) from Eq (1) and Eq (2) by using
Mathematica's commands ?

*******************************************************
   Toshiyuki (Toshi) Meshii  meshii at mech.fukui-u.ac.jp
    Associate Professor, Department of Mechanical Engineering
    Fukui University, 3-9-1 Bunkyo, Fukui, 910-8507, JAPAN
     Tel & Fax +81-776-27-8468
*******************************************************






  • Prev by Date: simplex method software
  • Next by Date: Re: Real integrand->complex result.
  • Previous by thread: simplex method software
  • Next by thread: Re: Composing a stiffness matrix