Numerical investigation of turbulent mixed convection flow and heat transfer characteristics of 2 × 2 subchannels with spacer grids

In turbulent mixed convection conditions, flow and heat transfer can deteriorate under specific thus affecting the performance of safety system, which could imperil nuclear reactor. this paper, by analyzing velocity, temperature distributions, other thermal-hydraulic parameters, steady-state computational fluid dynamics approach with SST k–? turbulence model used in study was verified. Then, characteristics inside 2 × subchannels without spacer grids were investigated. The results showed that velocity profiles distorted capacity impaired due to influence buoyancy. Nusselt number ratio (Nu/Nuf) between forced increased increase Reynolds (Re) until unity but decreased increases Grashof (Gr) Buoyancy parameter (Bo*).