# .cmode.csv file

This file is an output file generated when Acoustic Complex Eigenvalue Analysis is run.

This file consists of four sections including Mass Fraction, Modal Assurance Criterion (MAC) – Structural, Modal Assurance Criterion (MAC) – Interface (Wet Surface), and Modal Assurance Criterion (MAC) – Fluid.

## File Creation

This file is created when YES is selected in the PARAM, FCACSV Bulk Data Entry for Acoustic Complex Eigenvalue Analysis.

## Mass Fraction

### File Format

**Column****Description**- Mode ID
- Complex mode ID
- Eigenvalue(R)
- Real part of eigenvalue
- Eigenvalue(I)
- Imaginary part of eigenvalue
- Frequency
- Frequency of modes
- Mass Fraction(S)
- Mass fraction (structural)
- Mass Fraction(F)
- Mass fraction (fluid)

## Modal Assurance Criterion (MAC) – Structural

### File Contents

Mapped Structural Modes:

- Coupled Mode ID
- ID of full eigenvector coupled mode (For example, mode
Α
_{1}). - Mapped Mode ID(S)
- ID of full eigenvector (EV) uncoupled structural mode.
- MAC(S)
- MAC values are calculated for: Coupled mode (Α
_{1}) EV corresponding to the only structural grids versus each full EV uncoupled structural mode (mode 1 to mode N, where N is the total number of uncoupled structural modes). - MAC_Wet(S)
- MAC value is calculated for: Coupled mode (Α
_{1}) EV corresponding to only the wet surface structural grids versus uncoupled structural mode (identified in the Mapped Mode ID(S) field) corresponding to the wet surface structural grids.

### File Format

**Column****Description**- Mapped Mode ID
- Mapped uncoupled structural mode ID
- Frequency
- Frequency of uncoupled structural mode
- Frequency Diff(S)
- Frequency Diff: Coupled mode – Uncoupled mode
- Frequency Diff(S) (%)
- Percentage of frequency difference
- MAC(S)
- Modal Assurance Criterion: Coupled modes (structural grids only) versus uncoupled full eigenvector structural modes (MAC)
- MAC_Wet(S)
- Model assurance criterion values for coupled modes versus structural
wetted modesImportant: These are modes of the wet surface structural grids for corresponding modes in the listed Mapped Mode ID(S) column.

## Modal Assurance Criterion (MAC) –Interface (Wet Surface)

### File Contents

Mapped Wetted Modes:

- Coupled Mode ID
- ID of full eigenvector coupled mode (For example, mode
Α
_{1}). - Mapped Mode ID(WS)
- ID of uncoupled structural mode corresponding only to structural grids of the wet surface.
- MAC(WS)
- MAC values are calculated for: Coupled mode (Α
_{1}) corresponding only to structural grids of the wet surface versus each uncoupled structural mode corresponding only to structural grids of the wet surface (mode 1 to mode N, where N is the total number of uncoupled structural modes).

### File Format

**Column****Description**- Mapped Mode ID(WS)
- Mapped uncoupled mode ID corresponding to the wet surface
- Frequency(WS)
- Frequency of mode ID corresponding to the wet surface
- Frequency Diff(WS)
- Frequency Diff: Coupled mode corresponding to the wet surface – Uncoupled mode corresponding to the wet surface
- Frequency Diff(WS) (%)
- Percentage of frequency difference
- MAC(WS)
- Model assurance criterion values for uncoupled modes corresponding to wet surface versus coupled modes corresponding to the wetted surface

## Modal Assurance Criterion (MAC) – Fluid

### File Contents

Mapping Fluid Modes:

- Coupled Mode ID
- ID of full eigenvector coupled mode (For example, mode
Α
_{1}). - Mapped Mode ID
- ID of full eigenvector (EV) uncoupled fluid mdoe.
- MAC(F)
- MAC values are calculated for: Coupled mode (Α
_{1}) EV corresponding to only the fluid grids versus each full EV uncoupled fluid mode (mode 1 to mode N, where N is the total number of uncoupled fluid modes).

### File Format

**Column****Description**- Mapped Mode ID(F)
- Mapped uncoupled fluid mode ID
- Frequency
- Frequency of uncoupled fluid mode
- Frequency Diff(F)
- Frequency Diff: Coupled mode – Uncoupled mode
- Frequency Diff(F) (%)
- Percentage of frequency difference
- MAC(F)
- Model assurance criterion values for fluid modes versus coupled modes