Unsteady flow analysis of two different arm stroke techniques in front crawl swimming using computational fluid dynamics

Bozkurt, Bilgehan
This study analyzes how the propulsive force is created by the hand and arm in front crawl swimming. To answer this question, 12 swimming cases with variations in swimming velocity and arm velocity are compared using three dimensional straight and elbow angled arm models by doing unsteady flow analysis with computational fluid dynamics (CFD). The results show that the straight arm model creates more propulsive force than the angled arm. The results also reveal that linear hand velocity must be faster than swimming velocity in order to create good amount of propulsive force. In addition, the push phase of swimming has higher propulsive force than the pull phase. From this perspective, this study emphasizes the preferred arm position and the right time for a swimmer to use their effort to create the maximum propulsive force during front crawl swimming.


Flow Around Helicopter Blade Tip Sections Using a 2D Particle Image Velocimeter Part I
Kahveci, Harika Senem (null; 2006-12-01)
The current study is an effort to better understand the viscous flow physics existing near helicopter blade tips at various angle of attack positions. A planar particle image velocimeter (PIV) was successfully integrated into the helicopter blade tip flow measurement system in a model hover stand The current study utilizes a 1200 mm (47.24 in) diameter scaled helicopter rotor blade system with a 'collective pitch control' capability for flow field measurements. Downwash and upwash behavior at the sections o...
Removing force indeterminacy in a Hooke joint mechanism by increasing and modifying its joints without causing singularities
Himmetoglu, S; Özgören, Mustafa Kemal (2004-04-04)
The aim of this study is to eliminate the force indeterminacy in a Hooke joint mechanism. It is known that the Hooke joint mechanism is an overconstrained mechanism, so it is impossible to determine some of the unknown reaction forces and moments with the available number of force and moment equations. With the aid of extra joint additions and joint modifications as proposed in this study, it becomes possible to eliminate this force indeterminacy. The addition of extra joints increases the number of links; ...
Hava Taşıtlarına Uygulanan Güçlendirilmiş Silindirik Bir Dış Deponun Yapısal Analizi
Taş, Caner; Yaman, Yavuz; Kayran, Altan (2003-10-01)
Bu çalışmada, hava taşıtlarına uygulanan güçlendirilmiş bir dış deponun yapısal özellikleri I-DEAS®CAD/CAM/FEM programı kullanılarak araştırılmıştır. Dış deponun üç boyutlu katı modeli yaratılmış ve iki boyutlu ince kabuk elemanlar ve üç boyutlu katı elemanlar kullanılarak sonlu eleman ağı oluşturulmuştur. Uygun sınır şartları atandıktan sonra, güçlendirmenin ve yüklemenin dış deponun yapısal davranışına olan etkisini araştırmak amacıyla değişik konfigürasyonlara...
Experimental and numerical investigation of flow field around flapping airfoils making figure-of-eight in hover
Başkan, Özge; Alemdaroğlu, Hüseyin Nafiz; Department of Aerospace Engineering (2009)
The aim of this study is to investigate the flow field around a flapping airfoil making figure-of-eight motion in hover and to compare these results with those of linear flapping motion. Aerodynamic characteristics of these two-dimensional flapping motions are analyzed in incompressible, laminar flow at very low Reynolds numbers regime using both the numerical (Computational Fluid Dynamics, CFD) and the experimental (Particle Image Velocimetry, PIV) tools. Numerical analyses are performed to investigate the...
Swing up and stabilization of rotary inverted pendulum by using on-off type of cold gas thruster actuators
Silik, Yusuf; Yaman, Ulaş; Department of Mechanical Engineering (2019)
In this study, swing up and stabilization of on/off type of cold gas thruster driven inverted pendulum is accomplished. First, pulse width modulator (PWM) design method is generated to obtain quasi-linear thrust output from on/off type of thruster. Than, single axis angle controller is designed. Designed angle controller and PWM scheme are tested and verified on single axis angle control test setup. Finally, an other freedom is attached to single axis test setup and rotary inverted pendulum (Furuta Pendulum...
Citation Formats
B. Bozkurt, “Unsteady flow analysis of two different arm stroke techniques in front crawl swimming using computational fluid dynamics,” M.S. - Master of Science, Middle East Technical University, 2021.