Spreading of Oil Spilled under Ice

Abstract

A new set of equations is presented to describe the process of oil spreading under ice in calm waters. These equations consider the gravity (buoyancy)‐inertia phase, the gravity (buoyancy)‐viscous phase, and the termination of spreading during the buoyancy—surface‐tension phase. The derivation considers both the constant discharge mode and the constant volume mode. Therefore, a complete description of the spreading phenomena from the time of initial spill to the termination of spreading is presented. Laboratory experiments have been conducted using both real ice covers in a cold room and artificial ice covers. The experiments included different ice‐cover roughnesses from smooth to rough, oils of different viscosities, and a variety of discharge conditions. The experimental data show close agreement with the theory. These equations can be used during cleanup or environmental impact assessment to estimate the area of an oil slick with respect to time.