Flooding of disc turbines in gas-liquid dispersions: A new description of the phenomenon

✍ Scribed by M.M.C.G. Warmoeskerken; John M. Smith

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 897 KB
• Volume: 40
• Category: Article
• ISSN: 0009-2509
• DOI: 10.1016/0009-2509(85)87023-8

✦ Synopsis

The flooding transition of a Rushton turbine operating in a gas-liquid system has been investigated. A clear definition for the phenomenon has been given. From a theoretical analysis it is shown that a linear relation between the gas flow number FI and the Froude number Fr describes the onset of flooding. This relation has been validated by experiments in various vessels up to 1.2 m diameter. The-results predict gas flow rates for the occurrence of flooding which are higher than others reported in the literature. This is explained provisionally in terms of the geometries used, especially the tank and impeller diameter, the impeller clearance and the liquid height. It seems that at the flooding transition the stable alternate cavity structure behind the blades breaks down, and that this is responsible for the observed jump in the gassed power demand. A cavity formation map has been constructed in which areas are indicated representing characteristic conditions of the two-phase flow around the impeller in the loaded and flooded regimes.