| 講演要旨： |
A new method is described for computing solutions to the wave equations for short waves that travel through the atmosphere over long distances. The method, "Wave Confinement," is based on the formation of nonlinear solitary waves that are only one to two grid cells thick but "live" on the computational grid, propagating indefinitely with no numerical diffusion. These can be used both to directly treat short time-domain pulses and to compute the phase and amplitude of a harmonic wave (in the eikonal approximation), including multiple passes past each grid node. Because these waves representsolutions to a linear wave equation, they must pass through each other with no change in amplitude or phase, even though the numerical formulation is nonlinear. This is shown numerically and proven in the Born approximation. |
