The influence of distance between impingement and effusion plates on heat transfer characteristics of impingement-effusion double wall was investigated numerically

and the validity was experimentally verified. Results show that

with the increase of gap distance

heat transfer characteristics increase firstly

and then decrease. The change of gap distance caused different developments of impinging jet and pumping effects

and also led to different heat transfer effects. It shows that fluid particles move in translational mode in most region

but in rotating mode near effusion hole and impinging hole. The stronger fluid particle rotating causes better heat transfer effect.