APPARATUS FOR DIRECTING PARTICLES IN A FLUID

摘要

There is disclosed apparatus for directing particles entrained in a fluid, comprising a chamber having a first wall, including means for generating a sound wave having a frequency .nu., and a second, opposite wall capable of reflecting the sound wave in which the first and second wall define a condui t for the passage of the fluid, and in which the thickness of the second wall is such that the path length of the standing wave in the second wall is a multiple of about 1/2 the wavelength .lambda.r of the sound wave therein.