AIRY STRESS FUNCTION FOR TWO DIMENSIONAL INCLUSION ...
AIRY STRESS FUNCTION FOR TWO DIMENSIONAL INCLUSION ...
AIRY STRESS FUNCTION FOR TWO DIMENSIONAL INCLUSION ...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
2<br />
2 2<br />
2<br />
⎛<br />
⎞ ⎛<br />
⎞<br />
4 ∂ 1 ∂ 1 ∂ ∂ 1 ∂ 1 ∂<br />
∇ φ = ⎜ 2 + + 2 2 ⎟ ⎜ 2 + + 2 2 ⎟ φ = 0.<br />
(2.1.8)<br />
⎝ ∂r<br />
r ∂r<br />
r ∂ θ ⎠ ⎝ ∂r<br />
r ∂r<br />
r ∂ θ ⎠<br />
The plane problem again is formulated in term of the Airy stress function,<br />
φ( r , θ)<br />
, with a single governing biharmonic equation as required.<br />
2.2 Complex Variable Methods<br />
A complex variable z is defined by two real variables x and y<br />
This definition can also be expressed in polar form by<br />
z = x + iy.<br />
(2.2.1)<br />
Figure 2-2 Complex Plane.<br />
z r i re i<br />
= (cosθ + sin θ)<br />
=<br />
2 2<br />
where r = x + y known as the modulus of z and<br />
θ =<br />
−1<br />
tan ( y / x) the argument<br />
9<br />
θ<br />
(2.2.2)<br />
z x iy re i − θ<br />
= − = . (2.2.3)<br />
z is the complex conjugate of the variable z