An impingement cooling on a flat surface by using circular jet with longitudinal swirling strips

This work presents and discusses the results of an experimental investigation of the heat transfer between the constant-heat-flux test plate and the impinging jets. The round jets with/without swirling inserts are used. Smoke flow visualization is also used to investigate the behavior of the complicated flow phenomena under the swirling-flow jet for this impingement cooling. The effects of flow Reynolds numbers (500<=Re<=27,000), the geometry of the nozzle (BR, LSS and CSS), and jet-to-test plate placement (3<=H/d<=16) are examined.