Ridge Profile Measurements for Understanding Ridge Resistance

• Main Authors: Suominen, Mikko, Polojärvi, Arttu, Oikkonen, Annu
• Other Authors: Marine Technology, Department of Mechanical Engineering, Finnish Meteorological Institute, Aalto-yliopisto, Aalto University
• Format: Other/Unknown Material
• Language: English
• Published: POAC 2017
• Subjects: ridge profile; drilling; sonar; ridge keel; ridge sail; Aranda; Arctic; Sea ice
• Online Access: https://aaltodoc.aalto.fi/handle/123456789/35246

Ice ridges are the most difficult ice features that ships encounter in first-year ice conditions. Our understanding on ridge resistance on ships is currently limited, but we can assume that the keel of a ridge can have a significant impact to the resistance due to its large volume. In order to study the ridge resistance, we measured ridge profiles and recorded ship machinery and operational data during RV Aranda sea ice cruise in the Baltic Sea on spring 2016. This paper presents results from our ridge profile measurements made by drilling and with a sonar. We found a fairly good correspondence between these two methods. The maximum depth of the profiled ridges varied between 3 and 5 meters and the width of the cross sections from 10 to 25 meters. Peer reviewed