Evaluating The Thickness Of A Cyclopentane Hydrate Film Over A Sessile Water Drop Using PLIF And PIV

Abstract

The accumulation of hydrates presents an important flow-assurance challenge. Herein, we performed an experimental study to quantify the thickness of a hydrate layer growing laterally along the interface of a water drop submerged in the bulk phase of cyclopentane at sub-zero temperatures. Spatially-resolved velocity and temperature measurements in both liquid phases were taken independently using particle image velocimetry, one- or two-color planar laser-induced fluorescence. We found that the appearance of hydrates leads to a displacement of the temperature maximum away from the phase boundary, which is typically observed very close to the interface due to the recirculating motion of water inside the drop. Making an assumption that, when hydrates are absent, this recirculating motion is retained in time and the maximum position is, thus, unchanged, we conclude that this shift should indicate the hydrate layer should mostly protrude into the drop, and its thickness was evaluated to be around 0.38 mm.