Share
Export Citation
Fluid flow resistance through hemispherical dimpled plates in parallel and zigzag configurations
Salam N.
International Review of Mechanical Engineering
Q2Abstract
The application of hemispherical dimples in parallel and zigzag configurations on flat plates flowed with fluids is one of the rarest forms used in structural and transport engineering. It has been particularly studied on aircraft wing, turbine blade, golf balls and vehicle bodies with dents. For this reason, a study on resistance force on hemispheric dimpled in parallel and zigzag configuration on flat plates has been performed. The test piece has been made of acrylic in a total of 9 pieces with length of 30 cm, width 10 cm and thickness of 0.5 cm and dimpled ratio DR = 0.5. Dimples are arranged in rows numbered from 1 to 8. All the specimens are treated in 7 equal flow velocity rates from 8 m/s to 20 m/s. The study, which has taken place in laminar flow region with Reynolds number (Re) of 1.29×10^5 to 3.23×10^5, indicates that the use of hemispherical dimples in parallel and zigzag configuration reduces the resistance coefficient (Cd). For example, in the same Re=2.26×10^5 without dimples obtained Cd has been 0.0517 whereas on plates with dimples in parallel configuration, the smallest resistance coefficient obtained on 2 rows dimples has been of 0.0472. Dimpled plates in zigzag configuration have obtained Cd=0.0487 for single line dimple configuration. When compared with the plates without dimples, the percentage of resistance reduction coefficient for dimpled plates in zigzag configuration is 5.88%, while for dimpled plate in parallel configuration is 8.65%. This result shows that the use of parallel configuration is better than zigzag configuration.