Numerical Analysis of Diffusion Characteristics of Hazard and Noxious Substance (HNS) Spilled in Seawater

Abstract

Owing to huge casualty and environmental pollution caused by HNS (Hazardous and Noxious Substance) leakage, it is important to understand the diffusion characteristics of HNS and accurately estimate the propagation distance for coping withthe accidents at the early stage. The present study numerically investigates the diffusion characteristics of HNS spilled in seawater for different HNS materials and estimates the HNS propagation distances according to various accident scenarios. In this study, three-dimensional CFD simulations were conducted extensively with the use of the commercial code, ANSYS FLUENT (V. 17.0). Also, the VOF (Volume of Fraction) model was adopted for capturing the complex interfaces of HNS, rapidly changed with time. Moreover, the present study examines the influence of crack size, seawater velocity, and properties of HNS (floating/sinking) on the diffusion characteristics, and provides the numerical results of total spilled HNS volume, local HNS layer thickness, and maximum propagation distance. From the results, it was found that the maximum propagation distance is significantly affected mainly by the seawater velocity and the HNS property. Also, the current predictions would be useful in making such a strategic response to an HNS spill accident.