Steady-state wave propagation in simple and compound acoustic waveguides

A limiting absorption principle and corresponding existence theorem is presented for steady-state acoustic wave fields in simple and compound waveguides. The simple guides are semi-infinite cylinders, sectoral horns and conical horns. The compound guides are structures built by coupling one or more simple guides to a bounded cavity. The theory is developed under minimal regularity hypotheses about the waveguide walls. The class of allowable guides includes all the simple, but non-smooth, structures that arise in applications such as guides built from polyhedra and sections of cylinders, cones, spheres and other simple geometrical structures.