Particle Induced Turbulence Source Reference

The particle induced turbulence source models add more source terms to the continuous phase turbulence kinetic energy and dissipation equations. The models represent modification of turbulence due to the presence of a dispersed phase.

Table 1. Particle Induced Turbulence Models Reference
Model Names	Gosman
	Troshko and Hassan
	Tchen
	Generic
	LES Particle Induced Turbulence
Theory	See Particle Induced Turbulence Source.
Provided By	[phase interaction] > Models > Particle Induced Turbulence Source
Example Node Path	Multiphase Interaction > Phase Interactions > [phase interaction] > Models > LES Particle Induced Turbulence
Requires	In the continuous and dispersed phases: Material: one of Gas, Liquid, Multi-Component Gas, Multi-Component Liquid Viscous Regime: Turbulent Turbulence: Reynolds-Averaged Navier-Stokes or Large Eddy Simulation A Continuous-Dispersed Topology phase interaction is required. In the phase interaction: Optional Models: Particle Induced Turbulence Source or LES Particle Induced Turbulence
Properties	See Particle Induced Turbulence Source Properties. See LES Particle Induced Turbulence Model.
Activates	Field Functions	None.

Particle Induced Turbulence Source Properties

Use one of the following methods for calculating the particle induces turbulence source terms.

PIT Source Specification	Corresponding Properties/Method Nodes
Gosman This method adds source terms to the turbulent kinetic energy equation (see Eqn. (2478)) and to the turbulent dissipation equation (see Eqn. (2482)). Available only when the Turbulent Dispersion Force model is activated in the phase interaction.	None.
Tchen This method provides source terms to the continuous turbulent kinetic energy equation due to the interaction with particles, based on the theory of Tchen. Available only when the Turbulent Dispersion Force model is activated in the phase interaction.	C3 The dissipation calibration coefficient $C_{ε 3}$ in Eqn. (2485) defining the corresponding source term for the turbulent dissipation equation. Parameter $C_{ε 3}$ has a default value of 1.44, and you can adjust it independently of constants for other terms. Production Calibration Factor The coefficient $C_{0}$ in Eqn. (2483) defining the source term for turbulence energy or for Reynolds stress equations. This parameter is not part of the model derivation, but defaults to 1 and you can adjust it to test the sensitivity of the solution to this term. Crossing Trajectories Coefficient The calibration coefficient $C_{β}$ in Eqn. (2535), with a default value of 1.8. Turbulent Prandtl Number The coefficient $σ_{0}$ in Eqn. (2535), with a default value of 1.0, representing basic passive diffusivity.
Troshko and Hassan This method describes bubble induced turbulence effects. It adds a source term to the turbulent kinetic energy equation (see Eqn. (2472)) and another to the dissipation equation (see Eqn. (2474)). The method uses the Virtual Mass Force phase interaction model but if the model is not selected the virtual mass coefficients default to the value of a spherical bubble, which is given by Eqn. (2471).	C3 Selects the calibration constant $C_{3}$ for the dissipation term in Eqn. (2474). By default this constant is set to 0.45. Production Calibration Factor This parameter is not part of the model derivation, but defaults to 1 and can be used by the user to regulate the proportion of the source term in Eqn. (2473) that is used in the calculation.
Generic This approach combines the other particle-induced turbulence source methods into a generic one and provides the flexibility to modify the key properites which that cannot be adjusted in the other methods for calculating the particle-induced turbulence source terms. This adaptability makes the generic approach more appropriate for considering the multiscale effects associated with multiphase turbulence. Available only when the Turbulent Dispersion Force model is activated in the phase interaction.	TDF Modulation Parameter The modulation factor for the turbulence dispersion force contribution to particle-induced turbulence source. This is $C_{g}^{'}$ in Eqn. (2489), Eqn. (2494), and Eqn. (2510). Anisotropy Coefficient The anisotropy coefficient $A_{t}$ in Eqn. (2494). Applicable only to the Reynolds Stress Turbulence model and not taken into account in the computation of source terms for the other turbulence models. Dissipation Time Coefficient The dissipation time scale coefficient $τ_{ε}$ in Eqn. (2489). Method Selects one of the following methods for specifying the dissipation time scale: Constant Field Function Particle Relaxation Selects the particle relaxation method for solving the dissipation time coefficient, which is equivalent to the Troshko and Hassan method for PIT. Realizable Vortex Turnover Available only for EMP Mixture Turbulence with the $k - ϵ$ model. Selects the realizable vortex turnover method for solving the dissipation time coefficient. See Eqn. (2493). Vortex Turnover Selects the vortex turnover method for solving the dissipation time coefficient. See Eqn. (2492). C3 The dissipation calibration coefficient $C_{ε 3}$ in Eqn. (2489) and Eqn. (2510) defining the corresponding source term for the turbulent dissipation equation. $C_{ε 3}$ has a default value of 1.44 for the Realizable Vortex Turnover or Vortex Turnover dissipation time coefficient method, and a default value of 0.45 for the Particle Relaxation dissipation time coefficient method. Drag Force Modulation Parameter Specifies the drag force fraction $C_{g}$ in Eqn. (2488).

LES Particle Induced Turbulence Model

This model represents modification of turbulence due to the presence of a dispersed phase. This model is available only when the Large Eddy Simulation model is activated in the phase.

This model has no properties.