Room
The Room node is added by default and is used to define the mean free path model of each room (closed volumes) in a model. A Wall subnode is also added by default. Additional Wall subnodes and the Inward Energy Flux subnode are available from the context menu (right-click the parent node) or from the Physics toolbar.
Each room (volume) in a model needs a Room node with associated definitions of all wall properties. The volume and surface area of the room is calculated and used to determine the mean free path (depending on the model selected).
Mean Free Path Model
Select a Mean free path model — Ideal diffuse field (the default) or User defined. For User defined enter a Mean free path λ (SI unit: m). In most cases, the ideal diffuse field is valid and applicable. For the user defined case, the mean free path can, for example, be computed using a ray acoustics model.
For a tutorial model that computes the mean free path, see the Application Gallery model: Acoustic Mean Free Path in a Room
www.comsol.com/model/acoustic-mean-free-path-in-a-room-724915
Classical statistical room acoustic variables that are based on the room geometry and absorption properties of the walls are defined and can be used for postprocessing. See Statistical Model of Reverberation Time for details. They are:
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The total room absorption ade.A
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The Sabine reverberation time ade.T60_Sabine
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The Eyring–Norris reverberation time ade.T60_EN
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The Schroeder frequency of the room ade.f_Schroeder
Each room feature (say ade.room1, ade.room2, and so on) also has several room variables associated that may be plotted in postprocessing. They are:
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The room volume ade.room1.V
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The room surface area ade.room1.S
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The mean free path of the room ade.room1.lambda