Theoretical Investigation of the Influence of Different Chamber Geometries on the Agglomeration Capacity of Carbon Dioxide

摘要

This paper addresses the complicated process of carbon dioxide particle formation (agglomeration), which is essential for carbon dioxide snow blasting. Most effective process methods in this field possess a dedicated location where agglomeration is likely to occur. Research has shown that successful agglomeration is a key factor when cleaning or deburring with solid carbon dioxide. The following describes the mechanisms of carbon dioxide (CO_2) snow agglomeration inside this so-called agglomeration chamber. The elements of larger size, as well as an irregular shape directly lead to the increase of effectiveness. Therefore, it is necessary to determine how to improve this process for the purpose of dealing with difficult workpieces and materials and broaden the possibilities of carbon dioxide blasting. One of the main factors of agglomeration is turbulence. In short, the more turbulent activity that takes place, the better is the particle formation of solid carbon dioxide. Numerous geometries were created with different inserts, such as static mixers or angled tubes, in hope to increase turbulence. The basic idea is to implement these geometries in computational fluid dynamics (CFD) and finally proceed to an evaluation and comparison of the simulation results, in order to select the best candidates for optimization and realization.