Boundary Conditions on Bath Surface

When the gas flow rate Qg was 120 x 10 m /s and the top of the bath was free, there arose a swirl motion similar to the rotary sloshing typical of a bath in a cylindrical vessel subjected to external, horizontal, or vertical forced oscillation. This motion was termed the first type of swirl motion [12], 

The swirl motion could be stopped in one of the two ways, namely, by bringing a circular cylinder with an inner diameter of 78 x 10 m and an outer diameter of 80 X 10 m into contact with the bath surface or by bringing a flat circular disk with a diameter of 32 x 10 m and a thickness of 5 x 10 m into contact with the bath surface. The value of 32 x 10 m was the minimum disk diameter with which the swirl motion could be stopped completely for the experimental conditions investigated. The first option, using circular cylinder is referred to as the CAS model, while the second, utilizing the circular disk, is termed the disk model. 

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