Finite Element Techniques for Fluid Flow

76 THE FINITE ELEMENT TECHNIQUE

diagonal and upper diagonal elements in the form

diagonal /

column

3

(d)

-dummy

area

For instance the coefficients of element 2—equation (b)—would now

be stored in the form

p"

•

L,

2

2

*22

•

•

•

•

k

2

ΛΓ,2

•

•

•

2

*3.

2

j

*32

COMPUTER IMPLEMENTATION

In order to do the assemblage in the computer let us define the

following matrices

:

A(N,M) Global matrix, where N is the number of degrees of

freedom and M the band width.

S(N1,N1) Element matrix. This was our matrix K previously, but

we now call it S because K is an integer in FORTRAN.

y

y

•

•

/

•

•

7

•

• •

m

•

•

•

•

/

m

•

m

THE FINITE ELEMENT TECHNIQUE

77

I(N2,N3 ...