«Detailed Program

ID 126

Resolving an Idealized Fire Sprinkler Atomization Pattern with VOF Modeling and Adaptive Mesh Refinement

Karl V. Meredith
Research Division, FM Global
United States

Vuko Vukčević
University of Zagreb, Faculty of Mechanical Engineering and Naval Architecture
Croatia

 

Abstract:

This study presents the progress towards resolving the atomization pattern of an idealized fire sprinkler by using volume of fluid (VOF) modeling. Numerical modeling has been applied to understanding the atomization behavior of an idealized sprinkler geometry consisting of a 9.5 mm inner-diameter cylindrical nozzle and a flat, 25.4 mm diameter disk with a liquid flow rate of 0.71 L/s. The simulations have been performed with foam-extend-4.1 (a community driven fork of the OpenFOAM CFD software), using the ghost-fluid method and the isoAdvector scheme for interfacial reconstruction. In order to achieve efficient computations and adequately re-solve the flow, a newly implemented adaptive-mesh-refinement (AMR) scheme has been used. Comparisons of the liquid sheet breakup behavior in the near vicinity of the disk are shown for various AMR criteria. The computational efficiency is analyzed. This study represents a first step towards using AMR coupled with VOF modeling to adequately obtain injection patterns and provides a path to subsequently simulate realistic sprinkler geometries.