Study of heat transfer characteristics in a dimpled wall channel with impingement jets

An impingement heat transfer experiment was carried out in a dimpled wall channel of aeroengine inlet strut using transient thermochromic liquid crystal measurement technique. The effects of jet Reynolds number and jet angles on heat transfer distribution have been investigated. The results show that heat transfer is very high around the outlet slot along flow direction and on the trailing edge of the dimple. The heat transfer of dimpled wall is stronger than that of smooth wall. The average Nusselt number increases with the increasing of jet Reynolds number. At inclined inlet jet conditions, the heat transfer value in impacted wall is higher than the other side, and the highest value is obtained in stagnation region and trailing edge of the dimple. The inlet jet with 30° provides the strongest heat transfer performance while heat transfer near leading edge is the strongest at 15° conditions of all experiment angles.