Note: This discussion is about an older version of the COMSOL Multiphysics® software. The information provided may be out of date.
Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.
General Form PDE
Posted 31 août 2011, 12:44 UTC−4 Version 4.2 1 Reply
Please login with a confirmed email address before reporting spam
Hi
Is it possible to solve the following PDE ?
a*[d^2/dt^2(u)]+b*[d^4/dx^4(u)]=f(x,t) where 'a' and 'b' are constants and u=u(x,t)
By using the general form PDE
I cant define the 4th derivative in the Conservative Flux
Is there any other way ?
Thank you
Is it possible to solve the following PDE ?
a*[d^2/dt^2(u)]+b*[d^4/dx^4(u)]=f(x,t) where 'a' and 'b' are constants and u=u(x,t)
By using the general form PDE
I cant define the 4th derivative in the Conservative Flux
Is there any other way ?
Thank you
1 Reply Last Post 31 août 2011, 12:55 UTC−4
Please login with a confirmed email address before reporting spam
Posted:
1 decade ago
Hi
what about defining a new dependent variable that is the second derivative, and then derive it twice. You add a dependent variable, but you end up with only 2nd order equations + some BC's
This is a general math approach to resolve higher order PDE's all reasons to apply it with COMSOL too ;)
--
Good luck
Ivar
what about defining a new dependent variable that is the second derivative, and then derive it twice. You add a dependent variable, but you end up with only 2nd order equations + some BC's
This is a general math approach to resolve higher order PDE's all reasons to apply it with COMSOL too ;)
--
Good luck
Ivar