## Solver: sprayDyMFoam Description

sprayDyMFoam is a transient, multiphase solver for compressible, turbulent flows with spray particle cloud. Initially, this solver was designed to simulate the injection of high-pressure diesel, representing it as droplet parcels, employing the Lagrangian particle tracking technique. It is an extension of the sprayFoam solver additionally supporting the functionality of dynamic mesh motion.

The Eulerian-Lagrangian framework is used to describe the behavior of the flow. The Eulerian approach is used for continuous phase description (mass, momentum, and energy equations are solved), while the Lagrangian approach is used to describe the spray. The spray may represent many parcels with varying parcel properties, while the parcel represents many particles with identical particle properties.

The spray develops within the domain, influenced by the exchange of mass, momentum, and energy with the continuous gas phase. Consequently, the interactions between the two phases dictate the progression of the spray and the formation of the mixture.

The **PIMPLE** (merged PISO-SIMPLE) algorithm is used 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. Additionally, the solver can include porosity, buoyancy, radiation and **MRF** (Multiple Reference Frame) features in the flow simulation.

The solver can be applied for simulating fuel injection systems, rocket propulsion systems, and sprays for agricultural or pharmaceutical industries for situations where geometry changes.

## Solver: sprayDyMFoam Features

**Transient****Compressible****Multiphase - Lagrangian Particles**

- Species Transport
- Lagrangian Particles:
- Spray (Liquid Droplets)

- Chemical Reactions
- Evaporation and Boiling
- Combustion Modeling
- Dynamic Mesh Motion

- Laminar and Turbulent (RANS, LES, DES)
- Perfect Gas Model
- Pressure-Based Solver
- Rotating Objects:
- Multiple Reference Frames (MRF)
- Rotating Mesh Motion

- Passive Scalar
- Porosity Modeling
- Heat Transfer
- Heat Source
- Radiation
- Buoyancy
- Source Term (explicit/implicit)
- Transonic Flow
- PIMPLE Algorithm
- Solution Limiters:
- Velocity Damping
- Pressure Limit
- Temperature Limit

## Solver: sprayDyMFoam Application

**Automotive**

- Fuel Injection Systems

**Aerospace**

- Rocket Propulsion

**Agricultural**

- Pesticide and Fertilizer Sprays

**Pharmaceutical and Food Industries**

- Spray Drying

## Solver: sprayDyMFoam Species & Reactions Solvers Comparison

Species & Reactions Solvers In this group, we have included compressible (pressure-based) solvers that can be used to simulate: **Species Transport**, **Multicomponent Gas Mixtures**, **Chemical Reactions**, **Combustion**.

**Multicomponent**

- simpleReactingParcelFoam steady-state, multiphase particle clouds
- reactingParcelFoam transient, multiphase particle clouds

**Spray**

- sprayFoam transient, liquid particles only, dedicated to fuel spray combustion
- sprayDyMFoam extension of sprayFoam with DyM

**Coal**

- simpleCoalParcelFoam steady-state, coal particles only
- coalChemistryFoam transient, coal particles only

**Gas***

- reactingFoam fluids with minor density fluctuations (caused by pressure variance), no buoyancy
- rhoReactingFoam fluids with density variations due to reactions, no buoyancy
- rhoReactingBuoyantFoam extension of rhoReactingFoam with buoyancy forces

- * All solvers in this group are transient

- DyM - Dynamic Mesh

## Solver: sprayDyMFoam 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 | \(T\) [\(K\)] |

Species Mass Fraction | \(Y_i\) [\(-\)] |

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 | \(Avg\) \(Min\) \(Max\) |