### 3.2.12. Omega (Turbulence Eddy Frequency)

#### 3.2.12.1. Automatic Values

The default turbulence eddy frequency is calculated as:

| (3–5)

where:

is a non-dimensional constant

is the turbulent kinetic energy

is the kinematic viscosity

is the eddy viscosity ratio, which is set to 10 by default

#### 3.2.12.2. Recommended Values

Unless you have information about the turbulent frequency for your application, use the `Automatic` initial guess (which is to use an `Eddy Viscosity Ratio` of `10`).

#### 3.2.12.3. Manual Specification

Turbulence eddy frequency can be specified as a function of:

- `Epsilon` (that is, turbulence eddy dissipation)

- `Eddy Length Scale`

  | (3–6)

- `Eddy Viscosity Ratio`

  | (3–7)

Turbulence eddy frequency can also be specified directly as a CEL expression.

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