A numerical study of the effect of interwall spacing on turbulent flow in a corrugated duct

The effect of varying interwall spacing on periodic fully developed turbulent flow in a corrugated duct is studied numerically. The k-ε model is adopted for turbulent closure, and computations are performed for the ratio of the corrugation height to the interwall spacing ranging from 0.45 to 2.0, and for the corrugation angles of 30° and 45°. The Reynolds number ranges from 500 to 7000 while the Prandtl number is 0.7. The numerical procedure and implementation of the k-ε model is validated by comparing numerical results with the experimental data directly. The results are also compared with the numerical values obtained by using a two-layer low-Reynolds number turbulence model. At a given Reynolds number, an increase in the interwall spacing increases the size of the separated region. On the other hand the friction factor first increases with the decreasing interwall spacing, reaches its maximum value, and then decreases.