I have setup a geometry on comsol to investigate the transient behaviour of waves incident to it. I have modelled this by importing the geometry to comsol, surrounding it by a sphere and inserted a block to use as a plane wave radiation source that will be incident to one of the boundaries of the imported geometry.
I have set the boundaries of the geometry imported to sound hard, the sphere to exterior field calculation (which I think is the new name for perfectly matched layer) to avoid reflections. Set on of the boundaries of the block to plane wave radiation incident to the geometry opening.
The geometry opening consists of boundaries which I have assigned to sound soft boundary. Now the problem is that sound soft boundary reduces all incident pressure to 0 so I am never getting waves to enter the geometry. What boundary condtion should I assigned to this boundary in order to get waves to enter the imported geometry?
I have attached the project in order to understand better what I am talking about.