SIMULATION OF WET-SNOW ACCRETION BY AXIAL GROWTH ON A TRANSMISSION-LINE CONDUCTOR

When a snowflake, at air temperature just above the freezing point, impacts on a conductor, it fragments such that some of the mass adheres forming a snow deposit, and the remainder ricochets into the air stream. Thus the theoretical prediction of the shape of this accreting surface, evolving on the windward side of the conductor, crucially depends on the postulation of a law concerning the rate of adhesion or accretion during snowflake bombardment. Knowledge of the shape of the surface is, of course, required to evaluate lift, drag, and moment coefficients to be used in the study of the aeroelastic stability of the snow/conductor system. On simulation of the accretion process using a cosine law, the nonlinear snow evolution equation is formulated and solved by analytical and numerical techniques. The predicted snow shapes are found to be in excellent agreement with field observations on natural snow shapes.