RANS simulation of turbulent swept flow over a wire in a channel for core thermal hydraulic design using advanced eddy-viscosity models

Abstract

Modified cylindrical wire wrapped channel is analyzed using Reynolds-averaged Navier-Stokes (RANS) approach based on direct numerical simulation (DNS) results conducted by Ranjan et al. in 2010. There are four cases from 0 to 1,709 Reynolds number equivalent to crossflow bulk velocity with fixed 5,400 Reynolds number based on bulk velocity along the wire axis direction. Four mainly observed variables, velocity profiles in axial and crossflow direction, turbulence kinetic energy, recirculation zone and reattachment location, are distributed in DNS result. We selected standard k-ϵ models with three different constitutive relation and realizable k-ϵ model with two-layer approach as turbulence models for the assessment of design capabilities. We investigated the particular locations of flow characteristics especially in recirculation and reattachment point and these are fairly well matched with DNS results. Proceeding from fairly matched flow modeling results and economical computing resource of k-ϵ model, we could logically assume it has enough capability to engineering design tool of core thermal hydraulics.