heatEquationSolver

equationEvalFrequency

For steady simulations the default value for equationEvalFrequency is 10, which means if the flow solver is evaluated at every pseudo step, the heat solver is evaluated every 10 pseudo steps of the flow solution. This parameter essentially controls the feedback frequency from the solid to the fluid. It should always be greater than or equal to the equationEvalFrequency of the flow solver.

linearSolverConfig

linearSolverConfig controls the settings of the linear solver. Either absoluteTolerance or relativeTolerance can be used to determine the convergence of the linear solver. Together with maxIterations, they determine how much the heat equation solver residual converges in each pseudo step.