Turbulent heat transfer and hydrodynamics have been studied in concavely and convexly curved dimple in the range of Reynolds number from 1.3×105 to 3.1×105. The large scale single hemispherical dimple 50 mm diameter and 25 mm depth was arranged on a smooth concave or convex wall of curved rectangular-shaped passage. The fluid flow and heat transfer measurements, surface streamlines observations were performed within the flow curvature parameter δ**/R ranged from 0.002 to 0.007. The ‘tornado-like’ oscillating vortex bursting periodically out of dimple was registered in the experiments with a ‘curved’ dimple. This vortex structure is similar to that earlier observed in a ‘flat’ dimple. The surface curvature influences considerably the dimple heat transfer rate in both cases. It enhances heat transfer in a ‘concave’ dimple and reduces it in a ‘convex’ one, however the more remarkable effect is occurred in a concavely curved dimple. The correction factors describing the effect of curvature on average heat transfer in a ‘curved’ dimple have been obtained as a result of experimental study.
