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Acoustics

Commands of the acoustics chapter of the database, 9 entries. The status words are defined once, on the compatibility matrix, which says what each rests on and what the script builder does with it. Read it before this page: broken and removed are refusals, so a row here can be telling you the emitter will not write that command for that version.

ACOUSTIC_OBSERVERS_IMPORT

Phase setup, layout inline. Manual: SRC-003 p.373.

Reads observer locations from a CSV text file whose path follows on the next line. The manual describes the file's own format, a count line followed by that many comma-separated coordinate triples; that is the content of a file this package does not write, so it is paraphrased here and nothing validates it. Imported observers have no names, unlike those made by CREATE_NEW_ACOUSTIC_OBSERVER.

Argument Specification
file path
Version Status Evidence
25.000 documented SRC-749 p.333, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 p.368, same grammar as 26.120
26.101 documented SRC-725 p.372, same grammar as 26.120
26.120 documented SRC-003 p.373
26.121 documented SRC-740 p.376, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124

ACOUSTIC_SOURCES

Phase setup, layout inline. Manual: SRC-003 p.373.

Turns on the computation of acoustic sources during unsteady solver runs. IT MUST PRECEDE SOLVER INITIALIZATION, which the manual states and which is why this is a setup command in a post-processing chapter. Nothing here can enforce the ordering against a script the caller assembles by hand, so it is stated where a reader meets the command: enabling it afterwards costs a whole unsteady run and produces no sources to show for it. The manual gives the argument no name, the signature placeholder being the pair of values; mode is the database's house spelling for a two-valued switch.

Argument Specification
mode enum in
Version Status Evidence
25.000 documented SRC-749 p.333, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 p.368, same grammar as 26.120
26.101 documented SRC-725 p.372, same grammar as 26.120
26.120 documented SRC-003 p.373
26.121 documented SRC-740 p.376, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124

COMPUTE_ACOUSTIC_SIGNALS

Phase analysis, layout bare. Manual: SRC-003 p.374.

Computes the signal at every observer, from the acoustic sources recorded during the unsteady run. The one command in the chapter that does the work.

Version Status Evidence
25.000 documented SRC-749 p.334, same grammar as 26.120
25.100 documented SRC-748 p.347, same grammar as 26.120
26.000 documented SRC-747 p.346, same grammar as 26.120
26.100 documented SRC-741 p.369, same grammar as 26.120
26.101 documented SRC-725 p.373, same grammar as 26.120
26.120 documented SRC-003 p.374
26.121 documented SRC-740 p.377, same grammar as 26.120
26.123 documented SRC-751 p.381, unchanged from SRC-750 p.381
26.124 documented SRC-752 p.381, the SRC-751 file, carried from 26.123; not run on 26.124

CREATE_ACOUSTIC_SECTION

Phase analysis, layout keyword_block. Manual: SRC-003 p.374.

Builds an annular grid of observers in a plane and exports the signal at each of them, which is how a directivity pattern is produced rather than a signal at one point. IT CREATES AND EXPORTS IN ONE CALL, which is why STORAGE_PATH names a FOLDER rather than a file: one VTK file is written per observer per time step. That is potentially a very large number of files, the product of the two observer counts and the time steps set by SET_ACOUSTIC_OBSERVER_TIME, and no edition warns about it. The observers it creates are not the ones the rest of the chapter manages: nothing here deletes a section or lists what it made.

Argument Specification
frame int
plane enum in
offset float [simulation length units]
radial_observers int
azimuth_observers int
inner_radius float [simulation length units]
outer_radius float [simulation length units]
storage_path path
Version Status Evidence
25.000 documented SRC-749 p.334, same grammar as 26.120
25.100 documented SRC-748 p.347, same grammar as 26.120
26.000 documented SRC-747 p.346, same grammar as 26.120
26.100 documented SRC-741 p.369, same grammar as 26.120
26.101 documented SRC-725 p.373, same grammar as 26.120
26.120 documented SRC-003 p.374
26.121 documented SRC-740 p.377, same grammar as 26.120
26.123 documented SRC-751 p.381, unchanged from SRC-750 p.381
26.124 documented SRC-752 p.381, the SRC-751 file, carried from 26.123; not run on 26.124

CREATE_NEW_ACOUSTIC_OBSERVER

Phase setup, layout inline. Manual: SRC-003 p.373.

Appends one observer point at which the signal will be computed. THE COORDINATES ARE IN THE REFERENCE COORDINATE SYSTEM and the manual says so explicitly, which is worth recording because most of this database's position arguments take a frame index and this one does not: there is no way to give an observer a local frame.

Argument Specification
name str
x float [simulation length units]
y float [simulation length units]
z float [simulation length units]
Version Status Evidence
25.000 documented SRC-749 p.333, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 p.368, same grammar as 26.120
26.101 documented SRC-725 p.372, same grammar as 26.120
26.120 documented SRC-003 p.373
26.121 documented SRC-740 p.376, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124

DELETE_ACOUSTIC_OBSERVER

Phase setup, layout inline. Manual: SRC-003 p.373.

Deletes one observer by index. The manual defines the index as the observer's position in the application's own tree, which is a statement about the user interface rather than about anything a script can read back, so the index is not declared as a citation and nothing checks it. No all-form is stated: DELETE_ALL_ACOUSTIC_OBSERVERS is the separate command for that, so a -1 here is not documented anywhere and is not offered.

Argument Specification
observer_index int
Version Status Evidence
25.000 documented SRC-749 p.333, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 p.368, same grammar as 26.120
26.101 documented SRC-725 p.372, same grammar as 26.120
26.120 documented SRC-003 p.373
26.121 documented SRC-740 p.376, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124

DELETE_ALL_ACOUSTIC_OBSERVERS

Phase setup, layout bare. Manual: SRC-003 p.373.

Deletes every observer. A separate command rather than a sentinel value of the one above, which is why that one offers no all-form.

Version Status Evidence
25.000 documented SRC-749 p.334, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 p.368, same grammar as 26.120
26.101 documented SRC-725 p.372, same grammar as 26.120
26.120 documented SRC-003 p.373
26.121 documented SRC-740 p.376, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124

EXPORT_ACOUSTIC_SIGNALS

Phase analysis, layout inline. Manual: SRC-003 p.374.

Writes the computed signals at every observer to one file, the path on the next line. There is no per-observer export.

Argument Specification
file path
Version Status Evidence
25.000 documented SRC-749 p.334, same grammar as 26.120
25.100 documented SRC-748 p.347, same grammar as 26.120
26.000 documented SRC-747 p.346, same grammar as 26.120
26.100 documented SRC-741 p.369, same grammar as 26.120
26.101 documented SRC-725 p.373, same grammar as 26.120
26.120 documented SRC-003 p.374
26.121 documented SRC-740 p.377, same grammar as 26.120
26.123 documented SRC-751 p.381, unchanged from SRC-750 p.381
26.124 documented SRC-752 p.381, the SRC-751 file, carried from 26.123; not run on 26.124

SET_ACOUSTIC_OBSERVER_TIME

Phase setup, layout inline. Manual: SRC-003 pp.373-374.

Time window of the observer signal and how many steps it is sampled at. This is the OBSERVER's time axis and not the solver's: an acoustic signal arrives after a propagation delay, so the window a reader wants is not in general the unsteady run's own. The manual states no relation between the two and none is assumed here.

Argument Specification
initial_time float [s]
final_time float [s]
time_steps int
Version Status Evidence
25.000 documented SRC-749 p.334, same grammar as 26.120
25.100 documented SRC-748 p.346, same grammar as 26.120
26.000 documented SRC-747 p.345, same grammar as 26.120
26.100 documented SRC-741 pp.368-369, same grammar as 26.120
26.101 documented SRC-725 pp.372-373, same grammar as 26.120
26.120 documented SRC-003 pp.373-374
26.121 documented SRC-740 pp.376-377, same grammar as 26.120
26.123 documented SRC-751 p.380, unchanged from SRC-750 p.380
26.124 documented SRC-752 p.380, the SRC-751 file, carried from 26.123; not run on 26.124