Abstract
For the exploitation of seafloor massive sulfides, we have investigated the dynamic behavior of the jumper, a piece of flexible pipe that connects the seafloor mining tool to the subsea slurry pump.
In this article, we present the results of the experiment using a 1/5 reduced-scale model of the jumper. This experiment was carried out in Deep-Sea Basin. During the experiment, a slurry fluid was conveyed throughout the jumper’s model. In addition, an oscillator generated harmonic motion on the top end of the model. In terms of instrumentation, we installed load cells on the top and bottom ends of the model and a 3D visual measurement system tracked the motion of measurement stations attached to the model.
We present the experimental results measured by the 3D visual measurement system, loads cells, and differential pressure gauges in the cases where a vertically forced oscillation is imposed on the top of the jumper.
In this experiment, we could observe the effects of slurry on the jumper reduced-scale model. Since the slurry has a larger density than the single liquid phase, the slurry flow changed, as expected, the static shape of the jumper compared to a jumper conveying only water. The vertical top force average and differential pressure average increase with the volume concentration of solid, while their amplitudes increase quadratically with the forced oscillation frequency.
