Yongheng ZU, Peng LU*, Miao YU, Xiaowei CAO & Zhijun LI
State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China
Abstract：With the decline of Arctic sea ice, the dynamic process between sea ice and ocean is more important than before in the energy exchange. Concerning the influence of the ice-bottom topography on the drift of sea ice, it’s not clear that how the ridge keel drag force exerted by the ocean changes in the momentum balance of sea ice. Laboratory experiments are conducted to explain the local drag coefficient of the ridge keel varying with relative velocity of ice to water and keel shapes. The dimension analysis is used to obtain the relationship among local drag coefficient Cr, Reynolds number Re, dimensionless keel depth h0 and keel slope angle φ. Cr is only relevant to Re when Re<4000, also in the laminar region; and with increasing Re, Cr is a function of h0 and φ which are independent variables as the flow transition to the turbulent region. The parametrization formulae of Cr are given in the equation (6) and (8).
Keywords：ridge keel, drag coefficient, parametrization, Reynolds number