Flow Solver Test Case

[jbrillon]

Pull request to incorporate the addition of the abstract FlowSolver class derived from TestBase. The purpose of this class is to unify the codes/scripts within src/testing/ that simulate an unsteady flow case, where the different flow cases will be ran using the flow_solver.cpp and an appropriate .prm file.

This is accomplished within FlowSolver by:

• InitialConditionFunction virtual class (src/physics/initial_conditions/initial_condition.cpp)
• Addition of the flow solver parameter section (src/parameters/parameters_flow_solver.cpp)
• Parameterizing many of the test case code setup section that are typically repeated, such as: (1) Solution initialization, (2) Grid generation, and (3) Time advancement loops

As a first case, the Taylor Green Vortex (turbulent) flow case has been implemented, both inviscid and viscous; included in the class PeriodicCubeFlow derived from FlowSolver and InitialConditionFunction_TaylorGreenVortex class derived from InitialConditionFunction

Additional contributions:

• Cleanup and minor corrections to the ODE solver
• Runge Kutta order is now a parameter (default is 3)
• ODE solver iteration update is now done inside step_in_time() for easier use in src/testing/
• Bug fix in grid_study.cpp
• Creation of InitialConditionsLib found in src/physics/initial_conditions/
• Moved FreeStreamInitialConditions from src/physics/euler.h to src/physics/initial_conditions/initial_conditions.h
• Can set use_periodic_bc==true to suppress check_same_coords()

Current limitations:

• 2D and 3D cases only (because of Triangulation)

[dougshidong]

Consider opening up that PR soon if it's working. It's already starting to be on the bigger side.

[jbrillon]

@dougshidong Yep, that's the plan

[dougshidong]

Regarding format. First issue I'm tackling when I'm done with some of the PhD is: https://github.com/dougshidong/PHiLiP/issues/98

This will automatically format code such that spacing is not an issue anymore.

[dougshidong]

Looks like FlowSolver is currently quite specific to TGV. Especially since you are checking for some specific condition in between each step.