Analyzing the Stability of Floating Ice Floes

• Main Authors: Coutermarsh, Barry, McGilvary, Randy
• Other Authors: COLD REGIONS RESEARCH AND ENGINEERING LAB HANOVER NH
• Format: Text
• Language: English
• Published: 1994
• Subjects: Snow; Ice and Permafrost; Fluid Mechanics; *STABILITY; *HYDRODYNAMIC CHARACTERISTICS; *FLUID DYNAMICS; *MOMENT OF INERTIA; *ICEBERGS; VELOCITY; DENSITY; THICKNESS; ANGLE OF ATTACK; DEPTH; PRESSURE; GRAVITY; LEADING EDGES; ROTATION; PRESSURE DISTRIBUTION; FLOATING BODIES; HYDROSTATIC PRESSURE; FROUDE NUMBER; HYDRODYNAMIC CONTROL SURFACES; Ice; permafrost
• Online Access: http://www.dtic.mil/docs/citations/ADA292149; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA292149

This report describes an experimental study to measure the pressure caused by fluid acceleration beneath a floating parallelepiped block. Dynamic fluid pressure was measured at discrete points beneath the block for several flow velocities, flow depths, block angles of attack and block-thickness-to-depth ratios. The measured pressures were used to calculate block underturning moments, and a hydrostatic analysis was used to calculate a block righting moment. From this, a densimetric Froude undertuming criterion is presented. The measured hydrodynamic pressure distribution on the bottom of a single model ice floe is used to estimate the dynamic stability at three thickness-to-depth ratios. The energy-based analysis details the conditions required for instability, metastability and stability. At three thickness-to-depth ratios, block rotational inertia has the effect of reducing the Froude stability number by 5 to 10% over a completely static stability criterion. (MM)