How to solve the Laplace equation in a half disk with given boundary conditions?

Click For Summary
SUMMARY

The discussion focuses on solving the Laplace equation, specifically delta u = d²u/dx² + d²u/dy², within a half disk defined by the conditions 0 < r < R and 0 < phi < pi. The boundary conditions specify that the temperature on the bottom side of the disk is zero (u(x, y=0) = 0) and that on the upper side, it is defined as u(r=R, theta) = u0(phi) for 0 < phi < pi. The participant encountered difficulties in determining the constants after reaching a certain point in their solution process.

PREREQUISITES
  • Understanding of the Laplace equation and its applications in physics.
  • Familiarity with boundary value problems in partial differential equations.
  • Knowledge of polar coordinates and their use in solving problems in circular domains.
  • Experience with mathematical techniques for solving differential equations, such as separation of variables.
NEXT STEPS
  • Study the method of separation of variables for solving the Laplace equation.
  • Research techniques for determining constants in boundary value problems.
  • Explore the use of Fourier series in solving Laplace equations with non-homogeneous boundary conditions.
  • Learn about potential theory and its applications in solving problems involving Laplace's equation.
USEFUL FOR

Mathematics students, physicists, and engineers working on problems involving heat conduction and potential theory, particularly those dealing with boundary value problems in circular geometries.

EsponV
Messages
15
Reaction score
0

Homework Statement


Solve the Laplace equation: delta u = d2u/dx2+d2u/dy2
inside the half disk 0<r<R, 0<phi<pi
Temperature on the bottom side of the disk is zero, u(x,y=0)=0. Temperature on the upper side of the disk is u(r=R, theta) = u0(phi), 0<phi<pi



Homework Equations


I'm assuming the Laplace equation and the given bc conditions


The Attempt at a Solution


I attempted the solution, which I think up until this point is correct, but I've gotten stuck trying to figure out the constants.

http://img708.imageshack.us/img708/707/p2150074.jpg

Thank you all for your help.
 
Last edited by a moderator:
Physics news on Phys.org
I just got a email telling me I had a response, however I don't see it in the thread. Anyhow, the picture that only shows half the page of paper because that's all the work I had done on it. I got stuck at that point and wasn't sure how to go about calculating the unknown constants (if I had done everything correctly to that point).
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
2K
Replies
28
Views
3K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 26 ·
Replies
26
Views
5K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 6 ·
Replies
6
Views
5K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K