Research on Drag Reduction of Irrigation Delivery Pipeline
CHEN Xueli
WEI Zhengying
MA Ruijia
MA Shengli
MA Chao
Abstract：[Objective]Explore the drag reduction effect of riblet structure on the irrigation pipeline.[Method]The drag reduction effect of the riblet in the turbulent flow was simulated by SA and RNG k-?turbulence model, and compared with the results of Bechert's test, then the RNG k-?turbulence model was used to analyze the V-shaped riblet drag reduction at the scale of 0.1～1 mm for the irrigation pipeline, finally the LES turbulence model was used to explore the drag mechanism of the riblet structure.[Result]Compared with the SA turbulence mod-el, the RNG k-?turbulence model had the smaller error compared with the Bechert's test result, which was 4.6％, in other word, the RNG k-?turbulence model was more accurate. For a V-shaped riblet with the angle of 60° , when the riblet length was 0.5 mm, it had the best drag reduction effect on the irrigation pipeline, the drag reduc-tion rate was 7.17％, corresponding to the dimensionless pitch s+was 15.2, and dimensionless riblet size lg+was 10. There were small vortices in the riblets that might be one of the causes of the drag reduction in the turbulence.[Conclusion]The best drag reduction effect of the V-shaped riblet with an angle of 60° for the irrigation pipe-lines was 7.17％.
Keywords：irrigation pipelineriblet drag reductionnumerical simulationRNG k-?turbulence model
Publication Date：2018-01-01
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：6( 90-95 )