# MULTI_FIELD_MODEL

Specifies an equivalent material model for multi-field simulation.

## Type

AcuSolve Command

## Syntax

MULTI_FIELD_MODEL("name") {parameters...}

## Qualifier

User-given name.

## Parameters

- field_interation_models (string) [=none]
- List of names of field interaction models that are applied to this material model. The name must refer to a defined field_interaction_model entry.
- specific_heat_type (enumerated) [=linear]
- Type of blending of the different material specific heat.
- linear
- Linear combination of the individual material specific heat weighted by their respective volume fraction.

- viscosity_type (enumerated) [=linear]
- Type of blending of the different material viscosity.
- linear
- Linear combination of the individual material viscosity weighted by their respective volume fraction.

- conductivity_type (enumerated) [=linear]
- Type of blending of the different material conductivity.
- linear
- Linear combination of the individual material conductivity weighted by their respective volume fraction.

- density_type (enumerated) [=linear]
- Type of blending of the different material density.
- linear
- Linear combination of the individual material density weighted by their respective volume fraction.

- diffusivity_1_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 1).
- linear
- Linear combination of the individual material diffusivity for scalar 1 weighted by their respective volume fraction.

- diffusivity_2_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 2).
- linear
- Linear combination of the individual material diffusivity for scalar 2 weighted by their respective volume fraction.

- diffusivity_3_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 3).
- linear
- Linear combination of the individual material diffusivity for scalar 3 weighted by their respective volume fraction.

- diffusivity_4_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 4).
- linear
- Linear combination of the individual material diffusivity for scalar 4 weighted by their respective volume fraction.

- diffusivity_5_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 5).
- linear
- Linear combination of the individual material diffusivity for scalar 5 weighted by their respective volume fraction.

- diffusivity_6_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 6).
- linear
- Linear combination of the individual material diffusivity for scalar 6 weighted by their respective volume fraction.

- diffusivity_7_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 7).
- linear
- Linear combination of the individual material diffusivity for scalar 7 weighted by their respective volume fraction.

- diffusivity_8_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 8).
- linear
- Linear combination of the individual material diffusivity for scalar 8 weighted by their respective volume fraction.

- diffusivity_9_type (enumerated) [=linear]
- Type of blending of the different material scalar diffusivity (scalar 9).
- linear
- Linear combination of the individual material diffusivity for scalar 9 weighted by their respective volume fraction.

- immiscible_interface_type (enumerated) [=linear]
- Type of interface modelling for multi-field simulation.
- smooth
- The interface is diffused over a given distance with material properties transitioning smoothly between the different phases.

## Description

This command specifies models to be used to compute the average properties for the fluid in multi-field simulation.

```
MULTI_FIELD_MODEL( "my multi fluid model" ) {
field_interaction_models = {"my FIM"}
density_type = linear
specific_heat_type = linear
viscosity_type = linear
immiscible_interface_type = smooth
}
```