CO.sub.2 cleaning nozzle and method with enhanced mixing zones

Year	Description
1995	Invention patented by Lakhi Nandlal Goenka on May 4th, 1995. Abstract: An apparatus and method for cleaning a workpiece with abrasive CO.sub.2 snow operates with a nozzle for creating and expelling the snow. The nozzle includes an upstream section defined by a first contour for receiving CO.sub.2 in a gaseous form. The nozzle also includes a downstream section for directing the flow of the CO.sub.2 and the snow toward the workpiece, with the downstream section having a second contour optimized for supersonic flow of the CO.sub.2. The nozzle includes a throat section, interposed between the upstream and downstream sections, for changing the CO.sub.2 from the gaseous phase to an intermediate mixture of CO.sub.2 gas, liquid and snow within the downstream section at a speed of at least Mach 1.1. A turbulence cavity section is interposed between the throat section and the downstream section for inducing both turbulence within the CO.sub.2 gas flowing therethrough, thereby increasing the nucleation and agglomeration of the CO.sub.2 within a snow zone defined within the downstream section. The throat, upstream, turbulence cavity and downstream sections of the nozzle may be manufactured from silicon micromachined surfaces.
Source: selected by the editor from original sources.

Invention: CO.sub.2 cleaning nozzle and method with enhanced mixing zones