How the drag forces that act on bodies in a fluid?
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Drag forces that act on bodies in a fluid are important for understanding the dynamics of solid bodies in viscous fluids and have applications in engineering and fluid mechanics. The drag force is determined by factors such as the shape of the body, the velocity of the body, and the interaction between the body and the fluid. Experimental and theoretical investigations have been conducted to study drag forces on bodies of different shapes and at different velocities in viscous fluids . In the case of finite-sized and time-deformable bodies, such as flapping flyers or undulatory swimmers, the understanding of driving/dissipation interactions is more complex due to the changing shape of the body and the role of local drag . A simple model based on kinetic theory has been proposed to estimate drag forces on bodies moving through rarefied gases, providing accurate results and making it suitable for introductory courses . The circulation around two-dimensional objects and the emergence of vortices behind blunt bodies also contribute to drag forces . The geometry of the incoming flow can also affect the hydrodynamic drag of a body, but the confinement, contraction, and expansion of the flow have a limited impact on the drag force .
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06 Nov 2019 1 Citations | The paper suggests that drag forces on two-dimensional objects in a fluid can be derived from the circulation naturally maintained around the objects. The circulation generates a velocity field that attracts fluid particles towards the object, resulting in both lift and drag forces. The paper also discusses the drag generated by vortices behind blunt bodies. |
7 Citations | The paper discusses a simple model based on kinetic theory to estimate the drag force on a body moving through a rarefied gas, where fluid mechanics assumptions do not apply. It does not provide information on drag forces in general fluids. |
6 Citations | The paper does not provide a direct answer to the question of how drag forces act on bodies in a fluid. The paper focuses on the effect of gas flow geometry and turbulence on the hydrodynamic drag of a body, specifically a sphere. It discusses the early drag crisis phenomenon and the influence of turbulence on drag. |
| The paper discusses the role of drag forces in animal locomotion, particularly in flapping flyers and undulatory swimmers. It mentions that drag forces have two different facets, contributing to both global dissipation and driving forces. However, it does not provide a detailed explanation of how drag forces act on bodies in a fluid. | |
| The paper discusses the drag force acting on bodies moving in viscous fluids, but it does not provide specific details on how the drag forces act on these bodies. |
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