Author(s): Robert Ettema; Zhiming Chen; Yong Lai
Linked Author(s): Robert Ettema
Keywords: No Keywords
Abstract: This paper addresses the problem of frazil-ice blockage by an offshore, submerged water intake in frigid waters. It is well known that such intakes are potentially prone to ice blockage by frazil ice, and possibly by slush or brash ice drawn with flow to the intake. However, little is known about how intake geometry and size influence intake performance with respect to frazil ice. Presented are findings from a numerical model, and an ice-tank model, of flow-field behavior and frazil-ice ingestion by an intake located offshore. The intake form considered comprises a conical inlet, fitted optionally with an elevated cap, and connected to a shoreward pipeline. The ice-tank experiments are unique, insofar that experiments involving frazil ice have not before been done at the scale of the present experiments. The numerical and the ice-tank findings show that an elevated cap placed above the intake may substantially reduce the amount of frazil ice ingested by a submerged, conical intake.