Prescribed Acoustic Fields

The condition allows the user to prescribe one or more of the dependent variables at a boundary. When specifying (constraining) the dependent variables for the linearized Euler equations, it is necessary to not under-constrain the system. Typically, this requires defining both the density and pressure, defining the velocity, or defining all three at the same time.


	For systems that can be assumed isentropic, where the acoustic changes in the entropy are zero, enter an expression for the pressure p_user and the density p_user/lef.c0^2. This corresponds to the classical relation . This is also achieved using the Pressure (Isentropic) condition.

Prescribed Values for Acoustic Variables

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ρp (SI unit: kg/m3).

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(SI unit: m/s). If this check box is selected, choose one or more of these additional check boxes: upx, upy, or upz (for 3D components).

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pp (SI unit: Pa).

Constraint Settings

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