Effects of The Presence of Protrusions on The Air-Water Distribution in Parallel Vertical Channels

Uniform fluid and phase distribution is essential for efficient operation of engineering equipment such as plate heat exchangers, reactors, mixers where two phases are flowing together. Even though the principles of single phase distribution in parallel channels have been studied for more than three decades, further work is needed when a mixture is present, since to date many process equipment still suffer from uneven distribution of phases inside them. In this paper an experimental investigation is devoted to establish the influence of the operating conditions and of the header geometry on the phase/mass distribution into parallel vertical channels. The study is carried out with air-water mixtures and it is based on the measurement of gas and liquid flow rates in individual channels. The liquid and gas superficial velocities range from 0.2-1.2 and 1.5-16.5 m/s, respectively. In order to control the flow distribution in the channels, the header has been modified by introducing a number of protrusion pipes, whose protrusion height can be varied. The effects of presence of the protruded pipes into the header are analysed in terms of liquid and gas flow ratios and normalised standard deviation of phases and the present results are compared with previous ones obtained in different conditions of header geometry.