Bin Wang¹, Dayong Li², Yuxin Qin^3,*

Molecular & Cellular Biomechanics, Vol.17, No.4, pp. 179-188, 2020, DOI:10.32604/mcb.2020.011050

Abstract Swimming, as a sport beneficial to body and mind, also has a place in international sports. For swimmers and coaches, it is always the most important to improve the propulsion and reduce the resistance during swimming. This paper briefly introduced the resistance of human body in swimming, described the dynamic resistance of human body in arm stroke, and then introduced the principle of micro disturbance method which was used for measuring the dynamic resistance in swimming. Finally, ten swimmers from school team and ten beginners were tested for the dynamic resistance in freestyle, backstroke and breaststroke when they swam with… More >

Tian Li^{1, *}, Xiaohan Zhang¹, Yao Jiang², Weihua Zhang¹

FDMP-Fluid Dynamics & Materials Processing, Vol.16, No.1, pp. 121-130, 2020, DOI:10.32604/fdmp.2020.07976

Abstract The so-called Evacuated Tube Train (ETT) is currently being proposed as a high-speed transportation system potentially competitive with airplane transportation. Aerodynamic resistance is one of the most crucial factors for the successful design of an ETT. In the present work, a three-dimensional concept ETT model has been elaborated. The aerodynamic characteristics of the subsonic ETT have been numerically simulated under different conditions. The train’s running speed varies from 600 km/h up to 1200 km/h, and the blockage ratio is in the range between 0.1 and 0.3. As the blocking ratio and running speed increase, the resistance of the head car… More >