Simcenter 3D Solutions
Differences between "Distributed Acoustic Volume Quadrupole" and "Acoustic Volume Quadrupole"?
This article explains differences between "Distributed Acoustic Volume Quadrupole" and "Acoustic Volume Quadrupole"
In Aero-acoustic analysis, users have access to both "Distributed Acoustic Volume Quadrupole" and "Acoustic Volume Quadrupole":
Both Quadrupole loads are writing out the same Nastran card. However, in order to simplify to create multiple subcases at once, SC3D introduced the Distributed Acoustic Volume Quadrupole. The Distributed Acoustic Volume Quadrupole is only available under the Distributed Quadrupole subcase.
For example, if you have 1000 cgns files and if you want to create 3 subcases with 1-500, 251-750 and 501-1000, you can: Either
Create three Direct Frequency Subcase
Create separate “Quadrupole” load in each subcase
In each quadrupole load, define the time/sample range as 1-500, 251-750 and 501-1000 manually
Solve the problem for the multi subcase
Create a single Distributed Quadrupoles subcase
In the subcase, in the time range tab, select 500 samples with 50% overlap
Create one Distributed quadrupole load
No need to define the time range again. This will create 3 subcases in the dat file
Solve the problem with this setup
So, both will give same results. The distributed one will make the life easier. You can still add Quadrupoles (not distributed one) under Distributed Quadrupole Subcase, but you will be defining the time range twice, therefore no need to do that. We recommend using distributed quadrupole subcase and load for the most user-friendly solution creation (less effort since it will automate it at the export).