Solver Settings

The Heat Transfer interfaces define an elliptic partial differential equation for the temperature, T, of the form:

with Dirichlet and Neumann boundary conditions at some boundaries:

In its basic form, the density, ρ, heat capacity, Cp, thermal conductivity, k, heat sources, Q, constraint temperatures, T0, and heat fluxes, q0, are all constant, which leads to a linear system. Here, linear solvers described in the next paragraphs are completely suited for the resolution.

However, nonlinearities can appear in the equation in the following cases:

•	The material properties — ρ, Cp, and k — have a temperature dependency.

•	The heat sources are not linear in temperature.

•	The Neumann boundary condition is not linear in temperature, hence

-	A convective cooling condition of type −n ⋅ q = h(Text − T) keeps the linearity of the problem when the heat transfer coefficient, h, is constant.

-	A radiative condition of type −n ⋅ q = εσ(Tamb4 − T4) is strongly nonlinear.

Different nonlinear solvers are also provided for these kinds of problems.

The information about default solvers given below are specific to the Heat Transfer interfaces when the Stationary and Time-Dependent studies are used. A comprehensive description of solver settings and corresponding theory are available in the Study and Study Step Types section.

See also Studies and Solvers