Influence of the outlet system parameters of a horizontal bulb pump unit on its performance characteristics

Results of an extensive experimental study conducted in eighties at the former Leningrad Polytechnic Institute are revised and analysed in context of some further research. The optimum length of straight outlet tubes with diffuser of circular cross-section and the outlet/inlet crosssectional area ratio are established. The optimum geometrical features of cranked type outlet tubes and the outlet tubes with diffuser cross-section transition from circular to square and rectangular ones are determined. Finally, the influence of the outlet conjunction channel slope on the pumping station efficiency is studied in detail.