Interior Normal Acceleration

The node adds a normal acceleration on an interior boundary and ensures that the pressure is noncontinuous here. Add this node from the submenu. The pressure has a so-called slit condition on this boundary. This boundary condition can be used to model sources as, for example, the movement of a speaker cone modeled as a boundary. The condition adds the normal part of an acceleration a0(t):

Alternatively, specify the inward acceleration an(t). The normal of the boundary is interpreted as pointing outward.

Select a : (the default) or .

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For enter values for the components of the a0 (SI unit: m/s2).

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For enter the value of the an (SI unit: m/s2) in the normal direction. Use a positive value for inward acceleration or a negative value for outward acceleration. The normal of the boundary points outward. The normal is depicted as a red arrow in the graphics window on the selected boundary.


	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.