# Biharmonic equation

1. Nov 12, 2013

### joshmccraney

hey pf!

does anyone here have a link (or perhaps would care to share some info) on how to solve the biharmonic equation in polar coordinates (or, at least rectangular coordinates): $$\nabla^4 \psi = 0$$ where $\psi = f(r,\theta)$

i should say i have already done the obvious searches but didnt understand wikipedia and wolfram simply gave the answer, which is great but curiosity still has me. does separation of variables really work here?

thanks!

2. Nov 12, 2013

### Staff: Mentor

See Transport Phenomena, by Bird, Stewart, and Lightfoot, example 4.2-1, p. 122.
Creeping Flow around a sphere.

3. Nov 13, 2013

### joshmccraney

thanks chestermiller! ironically enough creeping flow around a sphere is the reason for my inquiry! i appreciate it!