APORT
APORT, PortNum
, Label
, KCN
, PRES
, PHASE
, --, VAL1
, VAL2
,
VAL3
, VAL4
Specifies input data for plane wave and acoustic duct
ports.
-
PortNum
Port number. This number is associated with an exterior port or interior port previously specified by the SF and BF family of commands, respectively. The number must be between 1 and 50.
-
Label
PLAN
—
Incident plane wave.
RECT
—
Rectangular duct.
CIRC
—
Circular duct.
COAX
—
Coaxial duct.
LIST
—
List the port settings. If
PortNum
= ALL, list the port settings for all defined ports.DELE
—
Delete defined ports. If
PortNum
= ALL, delete all defined ports.-
KCN
A previously-defined local (
KCN
>10) or global (KCN
= 0) Cartesian coordinate system number used to specify the geometric properties of the duct. Defaults to the global Cartesian coordinate system (0). The local Z-direction must be the direction of wave propagation. The origin of the local coordinate system must be centered about the face of the duct port without considering symmetry.-
PRES
Zero-to-peak amplitude of the pressure. If blank, the port will appear as a matching impedance.
-
PHASE
Phase angle of the applied pressure in degrees. Defaults to 0.
- --
Unused field.
-
VAL1
,VAL2
,VAL3
,VAL4
Additional input. The meaning of
VAL1
throughVAL4
varies depending on the specifiedLabel
.Label
= PLAN:VAL1
—
angle from positive X-axis to positive Y-axis in the local Cartesian coordinates (
KCN
).VAL2
—
angle away from positive Z-axis in the local Cartesian coordinates (
KCN
).VAL3-VAL4
—
Not used.
Label
= RECT:VAL1
—
Width of the rectangular duct.
VAL2
—
Height of the rectangular duct.
VAL3
—
Mode index for pressure variation along the width (defaults to 0).
VAL4
—
Mode index for pressure variation along the height (defaults to 0).
Label
= CIRC:VAL1
—
Radius of the circular duct.
VAL2
—
Not used.
VAL3
—
Mode index for pressure variation along the azimuth (defaults to 0).
VAL4
—
Mode index for pressure variation along the radii (defaults to 0).
Label
= COAX:VAL1
—
Inner radius of the coaxial duct.
VAL2
—
Outer radius of the coaxial duct.
VAL3
—
Mode index for pressure variation along the azimuth (defaults to 0).
VAL4
—
Mode index for pressure variation along the radii (defaults to 0).
Notes
Use the APORT command to launch a specified analytic acoustic mode into a guided duct.
The low-order FLUID30 element does not support the higher
modes in the coaxial duct (Label
= COAX).
For more information, see Specified Mode Excitation in an Acoustic Duct in the Acoustic Analysis Guide, and Analytic Port Modes in a Duct in the Mechanical APDL Theory Reference.