The Classical PDE Interfaces

Many classical PDEs are instances of Coefficient Form PDEs. The classical PDEs have their own interfaces found under the Mathematics>Classical PDEs branch () when adding an interface. Classical PDEs can also be added to all of the forms of PDE interfaces as domain nodes.

The following Classical PDE interfaces and nodes are available. All of these have the same settings as The Coefficient Form PDE Interfaces but adapted to a classical PDE:

•	Laplace Equation

•	Poisson’s Equation

•	Wave Equation

•	Helmholtz Equation

•	Heat Equation

•	Convection-Diffusion Equation.

The classical PDEs are not available in axisymmetric geometries. You can then use a Coefficient Form PDE instead, but note that you must compensate for missing factors related to the curvature of the coordinate system. See Notational Conventions for more information.

• Compact and Standard Notations for Classical PDEs • Domain, Boundary, Pair, Edge, and Point Conditions for PDEs