Laboratory Study of Anchor Ice Growth

A counterrotating flume housed in a cold room was used to study anchor ice growth. The rate of anchor ice growth was monitored and quantified over time using a digital image processing system. The laboratory experiments were conducted over Froude numbers ranging from 0.18 to 0.76 using air temperatures of −15 and −20°C. The data suggest that the rate of anchor ice growth and the density of the resulting anchor ice have a dependence on the Froude number. The rate of anchor ice growth is observed to be a maximum at a Froude number of approximately 0.27. The qualitatively observed density of the anchor ice increases with increasing Froude number. The release of anchor ice is related to the Reynolds number; anchor ice was released for Reynolds number less than approximately 42,000, but remains attached for larger Reynolds numbers.