Experimental and Numerical Investigation of Drag Force at High Speed Diver Motion in Different Depths from Free Surface

In this study, the drag force exerted on diver body is investigated by computational fluid dynamic and then the results validity is compared with towing tank experiments. The final target of this research is to evaluate thruster power for diver to reach the high speed motion underwater. In the last decade, the low speed diver motion has been studied by researchers for sport purposes and improvement of diving time, while in this research authors have tried to increase diver speed up to ۱۰ ms-۱ by use of electrical thruster mechanism. The numerical simulations are done by computational fluid dynamics considering three dimensional two phase turbulent flow. The geometry of the swimmers' bodies was generated by ۳-D scanning and image modeling of real divers in experimental diving test. Different turbulent models might be applied in specific case but the favorable one (k– method) is selected for estimating the forces on the divers. The experiments are done by five divers and one mannequin with ۵ depths and ۹ speeds. The numerical simulation results agree well with those of experimental tests in range up to ۸ ms-۱ but because of lab limitations more results between ۸ ms-۱ and ۱۰ ms-۱ were not accessible.

Keywords:

Divers drag force , CFD , Towing test