Numerical simulation of flow and heat transfer from slot jets impinging on a cylindrical convex surface

Flow and heat transfer characteristics of slot jets impingement to a cylindrical convex surface are numerically investigated. Suitable turbulence models have been determined through comparison with the experimental data. Flow structures are described and impingement heat transfer characteristics are discussed. The effects of Re, H/B and D/B on single-slot jets impingement heat transfer are analyzed and heat transfer characteristics of multiple-slot jets are investigated. The results show that: Gas flows along the convex surface and boundary layer separation occurs in both single and multiple-slot jets impingement. A maximum stagnation Nu appears at H/B=8 and the local Nu decreases with increasing H/B in the region far away from the stagnation. The Nu in the stagnation region decreases with increasing D/B but the Nu is nearly the same in the region far away from the stagnation. Pressure gradient is an important factor on heat transfer enhancement. Correlations of the Nu _m for single-slot, double-slot and quadric-slot jets impinging on a convex surface are obtained. It indicates the effects of Re and D/B on Nu _m could become more important in less slot jets impingement.