Boundary Element Methods–Numerical Implementation - The Boundary Element Method with Programming - page 146

xsi= 2.0*Glcor(m)-1.0
dxdxb= 2.0
CASE (2)
xsi= 1.0 -2.0*Glcor(m)
dxdxb= 2.0
CASE (3)
dxdxb= 1.0
IF (nr == 1) THEN
xsi= -Glcor(m)
ELSE
xsi= Glcor(m)
END IF
CASE DEFAULT
END SELECT
CALL Serendip_func(Ni,xsi,eta,1,Nodel,Inci)
Call Normal_Jac(Vnorm,Jac,xsi,eta,1,Nodel,Inci,elcor)
dUe(i,n)= dUe(i,n) + Ni(n)*c1*Jac*dxdxb*Wi(m)
END DO &
Gauss_points1
END DO &
Subregions
!------------------------------------------
! Integration of non logarithmic term
!-------------------------------------------
Mi= 2
Call Gauss_coor(Glcor,Wi,Mi) ! Assign coords/Weights
Gauss_points2:&
DO m=1,Mi
SELECT CASE (n)
CASE (1:2)
c2=-LOG(Eleng)*c1
CASE (3)
c2=LOG(2/Eleng)*c1
CASE DEFAULT
END SELECT
xsi= Glcor(m)
CALL Serendip_func(Ni,xsi,eta,ldim,Nodel,Inci)
Call Normal_Jac(Vnorm,Jac,xsi,eta,ldim,nodel,Inci,elcor)
dUe(i,n)= dUe(i,n) + Ni(n)*c2*Jac*Wi(m)
END DO &
Gauss_points2
END DO &
Node_points1
END DO &
Colloc_points1
RETURN
END SUBROUTINE Integ2P
The above integration scheme is equally applicable to elasticity problems, except that
when integrating functions with Kernel U when P i is one of the nodes of the element we