In-Cloud Supercooled Droplets Distribution Effect on Ground Structural Icing

Abstract Better understanding of ground structural atmospheric ice accretion process is pivotal for the development of optimal and effective ice mitigations measures. To study the influence of the in-cloud supercooled water droplet distribution spectrum on the ground structural icing process, a circular cylinder is used as a reference object. Analyses are carried out using multiphase analytical model [International Organization for Standardization (ISO 12494)], computational fluid dynamics (CFD)-based multiphase numerical simulations, and field experiments in natural icing conditions. Aim of this study is to improve understanding about the influence of median volume diameter (MVD) and drop size distribution (DSD) on resultant ice accretion. Results show that compared to the numerical simulation results, droplet collision efficiency α 1 obtained using an analytical ISO model is always larger. At lower wind speeds, the error in α 1 obtained using MVD changes with the variations of the droplet distribution spectrum. Compared to DSD, ranging from Langmuir C to Langmuir J (Langmuir water droplet size distribution), the α 1 error of using MVD gradually increases. The icing rates obtained using MVD are smaller, and the iced area is narrower. Results from numerical and analytical models are also validated with the field experiments in natural icing conditions.