Effect of the Position of an Orifice with Respect to an Elbow on Counter-Current Flooding

Abstract

This paper presents experimental results on counter-current flow (CCF) and flooding in a test section containing a vertical and a horizontal run in which an orifice is placed. In particular, the influence of the position of various sized orifices with respect to the elbow between the vertical and horizontal runs is examined. The experimental technique used allowed not only the flooding limit to be determined, but also the entire partial liquid delivery region up to zero liquid penetration point to be determined as well. Experiments were also carried out for deflooding in order to study hysteresis effects. In general, it is observed that both the flooding limits and the delivered liquid flow rates decrease with decreasing the size of the orifice. It is also observed that the flooding limit seems to be independent of the position of the orifice. Furthermore, it is observed that when the orifice is closer to the elbow, the delivered liquid flow rate is lower for a given set of experimental conditions than when the orifice is far away from the elbow. Even though a hysteresis effect is present in the experiments, i.e., the deflooding point occurs when the superficial velocity is significantly lower than the gas superficial velocity at the flooding point, the deflooding points are seen to closely follow the partial delivery curve for all the cases studied.