# ACINT

I/O Options and Subcase Information Entry Used in the I/O Options section or in frequency response (direct and modal) subcases to request acoustic intensity at the fluid grids.

## Format

ACINT (format) = option

## Definitions

Argument Options Description
format <H3D, PCH, blank>
H3D
Results are output in Hyper3D format (.h3d file).
PCH
Results are output in Punch format (.pch file).
Blank (Default)
Results are output in all active formats for which the result is available.
option <YES, ALL, NO, NONE, SID>
YES, ALL (Default)
Intensity is output for all acoustic grids.
NO, NONE
Intensity is not output.
SID
If a set ID is given, the acoustic intensity is output only for the fluid grids listed in that set.

1. The expression for acoustic intensity is related to the nodal pressure ( $p$ ) and the complex conjugate of the particle velocity ( $\nu *$ ), given by:(1)
$1\left(\Omega \right)=\frac{1}{2}pv*$