Experimental and numerical study on the efficiency of hydraulic collection utilizing two different suction inlets

Abstract

Hydraulic collection has been shown to be a promising technology in deep sea mining. However, the efficiency of hydraulic collection is affected by many factors. For understanding the effect of inlets distinct from shapes on collecting efficiency, a series of upward pumping experiments was conducted on spheres. Flow fields at different inlets were described by numerical simulation and compared to uncover the influence of inlet shape on collecting the sphere. The experimental results indicate that straight cylindrical pipe with flanged inlet has a higher efficiency in collecting than the straight cylindrical pipe without flanged inlet. The numerical results show that the restriction of the flanged inlet lead to a larger area of negative pressure on the top of the sphere, which means a bigger upward force.