Coal-Water Mixture : 1st Report, Basic Disintegration Mechanism and Spray Characteristics

Abstract

Consecutive studies has been carried out for the purpose of clarifying spray performances of highly concentrated CWM and for obtaining a guide for the design of practical twin-fluid atomizers. Disintegration mechanisms and spray characteristics were investigated using plain-jet type of CWM atomization, and compared with those of single phase liquids. Furthermore, those disintegration phenomena and spray characteristics were considered in the proposed disintegration model. In the disintegration of a CWM jet by high speed air, atomization phenomena become similar to those of low viscosity liquids. Spray is generated basically by the tearing off of irregularly shaped small drops from the jet surface and splitting up of the unstably fluctuating jet into spherical drops. The change in Sauter's mean diameter of spray for air velocity changes its tendency at a certain velocity.