Author(s): Robert Ettema; Andreas Mueller; Alfred G. Cook
Linked Author(s): Robert Ettema
Keywords: No Keywords
Abstract: Presented here are observations on the growth of six sheets of urea ice on a relatively small ice basin (0.51-m deep, 0.9-m wide and 5.8-m long). Detailed measurements of the evolution of temperature profile in the solution and ice sheet were taken using a vertically-staggered array of thermistors which were located through each ice sheet, in the underlying solution, and in the air above the basin. Growth rate, heat fluxes and crystal structure were monitored for each ice sheet during its growth and warming periods. For relatively rapid ice sheet growth on ice basins, it is usually desirable to have a low air temperature and a solution temperature close to the solution's freezing temperature. However, for small ice basins that are not well insulated, supercooling of the solution may limit the ice sheet thickness that can be attained with the ice crystal structure usually required for scale modeling. Beyond this thickness, ice sheet growth is accompanied by the irregular growth of randomly spaced dendritic crystals, which may subsequently become included in the lower columnar layer of the ice sheet and noticeably affect its strength and frictional properties.