Materials:
Introduction: Chap 1
- What is a PDE?
- What is a solution of a PDE?
- Some commonly used PDE examples
- IVP and BVP
- Classification of PDEs
- Mathematical: order, linearity (quasi-linear),
constant/variable coefficient(s), homogeneity/source terms
- How to classify second order linear PDEs? hyperbolic,
elliptic, parabolic (compare with quadratic curves)
- Physical: advection, heat, wave, elliptic equations;
Laplace/Poisson equations
- Well-posedness of PDES, existence, uniqueness, and sensitivity
of PDES
- Solution techniques
- Analytic: PDE--> ODE
- Approximate semi-analytic; numerical solutions
Advection and first order linear PDEs (1D)
- Advection equation: u_t + a u_x = 0
- Method of changing variables: a u_t + b u_x + c u = f(x,t)
--> U' + c U = F(\xi,\eta), an ODE.
- Method of characteristics, homogeneous system, a u_t +
p(x,t) u_x = 0.
- General solutions: u(x,t) = f(x-at)
- Cauchy problem: u(x,t) = u_0(x,t)
- Bounded domain, where should we have a boundary
condition? ( \bar{x} - x = a (\bar{t}- t)) solve for
bar{x} or \bar{t}
Wave equations (1D)
- General solution: u(x,t) = F(x-at) + G(x+ at)
- Solution to Cauchy problems: D'Alembert's formula: u(x,t) = (
f(x-at ) _ f(x+at))/2 + (\int_{x-at}^{x+at} g(s) ds )/(2a)
- Normal modes: sin (x pi x/L) sin (x pi c t); sin
(x pi x/L) cos (x pi c t) and solution to specific initial
conditions.
Orthogonal functions and Sturm-Liouville problems (basis
for separation variables)
Series solution for PDEs on bounded domain in Cartesian
coordinates
Series solution for PDEs on bounded domain in polar and
spherical coordinates
Fourier transform and Laplace transforms
Numerical solutions for PDEs on bounded domain