ABSTRACT

Geometric mapping from the natural coordinate to the physical coordinate is

(6.1.17)

The Jacobian becomes

length.

Derivatives of the shape functions, Eqs. (6.1.13) through (6.1.15), are

dH1(C,) = _!_ dH1 = 2_(2(, _ 1) dx J dC, hi

(6.1.19)

(6.1.20)

QuadrilateralElements

Figure6.2.1BilinearElementintheNaturalCoordinate

dH3(0=_!_dH3=_!_( 2 ~+1) dxJd~h;

(6.1.21)

Theshapefunctionsforthebilinearisoparametricelementaregivenbelow:

(6.2.1)

1 H2(~,TJ)=4(1+0(1-TJ)(6.2.2)

1 Jfs(~,TJ)=4(1+~)(1+TJ)(6.2.3)

1 H4(~,TJ)=4(l-0(1+TJ)(6.2.4)

forthenodesshowninFig.6.2.1.Theseshapefunctionsaredefinedintermsofthe normalizednaturaldomain(i.e.-1:S~:S1and-1:::;TJ:S1).