## Solver: sonicDyMFoam Description

sonicDyMFoam is a pressure-based solver designed for transient simulations of compressible flow. It handles laminar and turbulent, single-phase flows with temperature and density variations (it solves the energy equation). It is an extension of the sonicFoam solver additionally supporting the functionality of dynamic mesh motion.

The solver uses the **PIMPLE** (merged PISO-SIMPLE) algorithm for pressure-momentum coupling. This algorithm leverages the strengths of both **PISO** and **SIMPLE** methods for pressure-velocity coupling, ensuring robustness in handling transient flows with large time steps. This approach is supplemented by under-relaxation techniques to secure convergence stability. It supports both Multiple Reference Frame (**MRF**) and porosity modeling and allows easy integration of passive scalar transport equations and source terms.

The dynamic mesh capabilities of this solver expand its scope for analyzing moving objects. In the aerospace aerodynamics it can simulate the effect of moving control surface (e.g. flaps) on the aircraft’s performance. The solver can simulate the turbine blade fluttering in the turbomachinery industry. For the rocket exhaust systems, it can be used to analyze the changing geometry of the nozzle.

## Solver: sonicDyMFoam Features

**Transient****Compressible****Single-Phase**

- High-Speed Aerodynamics
- Transonic Flow
- Supersonic Flows
- Pressure-Based Solver
- Shock Waves Capturing
- Dynamic Mesh Motion

- Laminar and Turbulent (RANS, LES, DES)
- Equation of State Models
- Rotating Objects:
- Multiple Reference Frames (MRF)
- Rotating Mesh Motion

- Passive Scalar
- Porosity Modeling
- Heat Transfer
- Heat Source (energy source therm)
- Source Term (explicit/implicit)
- PIMPLE Algorithm
- Solution Limiters:
- Velocity Damping
- Temperature Limit

## Solver: sonicDyMFoam Application

**Aerospace Industry**

- Flight Control Systems Movement and Aircraft Performance

**Wind Tunnel Simulations**

- Moving Objects in the Wind Tunnel

**Exhaust Systems**

- Changing Geometry of the Nozzle

## Solver: sonicDyMFoam Compressible Solvers Comparison

Compressible Solvers In this group, we have included single-phase, pressure and density-based solvers that can handle flows with significant variations in density, mostly applicable for and **high-speed aerodynamics** (**Ma > 0.3**)

**Subsonic / Transonic, Steady-State, Ma < 1**

- rhoSimpleFoam steady-state, pressure-based, small density changes
- overRhoSimpleFoam extension of rhoSimpleFoam with Overset

**Subsonic / Transonic, Transient, Ma < 1**

- rhoPimpleFoam transient, pressure-based, small density changes, DyM
- overRhoPimpleDyMFoam extension of rhoPimpleFoam with Overset, DyM

**Transonic / Supersonic, Pressure-Based, Ma > 1**

- sonicFoam transient, pressure-based, shock waves
- sonicDyMFoam extension of sonicFoam with DyM

**Transonic / Supersonic, Density-Based, Ma > 1**

- rhoCentralFoam transient, density-based, shock waves
- rhoCentralDyMFoam extension of rhoCentralFoam with DyM

- Ma - Mach Number
- DyM - Dynamic Mesh
- Overset - also known as Chimera Grid (Method)

## Solver: sonicDyMFoam Results Fields

This solver provides the following results fields:

**Primary Results Fields**- quantities produced by the solver as default outputs**Derivative Results**- quantities that can be computed based on primary results and supplementary models. They are not initially produced by the solver as default outputs.

**Primary Results Fields**

Velocity | \(U\) [\(\frac{m}{s}\)] |

Temperature | \(T\) [\(K\)] |

Pressure | \(p\) [\(Pa\)] |

**Derivative Results**

Density | \(\rho\) [\(\frac{kg}{m^{3}}\)] |

Vorticity | \(\omega\) [\(\frac{1}{s}\)] |

Mach Number | \(Ma\) [\(-\)] |

Courant Number | \(Co\) [\(-\)] |

Peclet Number | \(Pe\) [\(-\)] |

Stream Function | \(\psi\) [\(\frac{m^2}{s}\)] |

Q Criterion | \(Q\) [\(-\)] |

Wall Functions (for RANS/LES turbulence) | \(y^+\) [\(-\)] |

Wall Shear Stress | \(WSS\) [\(Pa\)] |

Wall Heat Flux | \(\phi_q\) [\(W/m^2\)] |

Turbulent Fields (for RANS/LES turbulence) | \(k\) \(\epsilon\) \(\omega\) \(R\) \(L\) \(I\) \(\nu_t\) \(\alpha_t\) |

Volumetric Stream | \(\phi\) [\(\frac{m^{3}}{s}\)] |

Passive Scalar | \(scalar_i\) [\(-\)] |

Forces and Torque acting on the Boundary | \(F\) [\(N\)] \(M\) [\(-\)] |

Force Coefficients | \(C_l\) [\(-\)] \(C_d\) [\(-\)] \(C_m\) [\(-\)] |

Average, Minimum or Maximum in Volume from any Result Field | \(Avg\) \(Min\) \(Max\) |