Template:Equations for a beam
From WikiWaves
There are various beam theories that can be used to describe the motion of the beam. The simplest theory is the Bernoulli-Euler Beam theory (other beam theories include the Timoshenko Beam theory and Reddy-Bickford Beam theory where shear deformation of higher order is considered). For a Bernoulli-Euler Beam, the equation of motion is given by the following

where β(x) is the non dimensionalised flexural rigidity, and γ is non-dimensionalised linear mass density function. Note that this equations simplifies if the plate has constant properties (and that h is the thickness of the plate, p is the pressure and ζ is the plate vertical displacement) .
The edges of the plate can satisfy a range of boundary conditions. The natural boundary condition (i.e. free-edge boundary conditions).

at the edges of the plate.
The problem is subject to the initial conditions

