Viscothermal wave propagation in a circular layer with a partially open and partrally closed boundary

The so called low reduced frequency model has been shown to be both an accurate and a relatively simple description of wave propagation in narrow tubes or layers, under small signal conditions. In this paper, the low reduced frequency model will be applied on a circular layer between a fixed surface and a rigidly translating plate. The outer circumference of the layer is partially closed (Neumann boundary condition) and partially open (Dirichlet boundary condition). A semi-analytical solution for this problem is used to calculate the volume flow that is generated by the squeezing motion of the plate, and the resulting force on the plate. The volume flow per unit force is evaluated for several boundary conditions