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Normal Acceleration
The Normal Acceleration adds an inward normal acceleration an(t). Mathematically, the condition adds the boundary condition:
Alternatively, specify the acceleration a0 of the boundary. The part in the normal direction is used to define the boundary condition:
This feature represents an external source term. It can also be used to manually couple acoustics with a structural analysis for modeling acoustic-structure interaction.
Normal Acceleration
Select a Type: Inward Acceleration (the default) or Acceleration.
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For Inward Acceleration enter the value of the Inward acceleration an (SI unit: m/s2). Use a positive value for inward acceleration or a negative value for outward acceleration.
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For Acceleration enter values for the components of the Acceleration a0 (SI unit: m/s2).
In transient models all sources need to be functions of time t in order to represent an acoustic signal. This can, for example, be a harmonic sine wave defined as sin(omega*t) or any other signal.