Oil Layer Flow around Skimming Vessels

ABSTRACT The flow of an oil layer around an advancing skimming vessel was investigated theoretically on the following assumptions: (1) the oil layer is so thin that the velocity distribution is uniform over the depth; (2) there is no shear and tension at the oil-water interface; and (3) the density difference between oil and water is so small that the elevation of the air-oil interface is negligible. The investigation showed that the oil layer flow is replaced by a supercritical flow in a shallow open water channel which is characterized by the densimetric Froude number in the ideal case of inviscid fluids with no interfacial tension. Tank tests have been carried out to verify the theoretical model and its simulation of an oil layer flow, using scale models of a mono-hull vessel. Similar models with different entrance angles have been tested, at varying ship speeds and oil layer thicknesses. The test results show that the theoretical model and the similitude are valid at lower densimetric Froude numbers, ...