Effect of tube structure on beam propagation when depressing thermal effect by blowing

The inner flow field’s influence on beam was simulated to study how to design the tube’s inner structure when blowing non-absorbing gas in them to depress thermal-effect of air. The beam-gas-effect model was adopted as well as a Z-like tube and a U-like tube were used in comparison. The results showed different inner structure of tube will produce different influence on beam. The U-like tube could hold the flow field smoother and had little influence on beam than the Z-like tube under the same blowing condition. This was because its flow velocity changed little in direction than the other one. However, the Z-like tube was a little better than the U-like tube when without blowing.