with speed increasing in high-speed trains, due to limitations of other types of brakes, aerodynamic brake has become an important braking method. in this task to make better use of brake’s panel different configurations are examined and the best panel shape which provides the reasonable drag coefficient is introduced. the results of simulations are carried out with the computational fluid dyna...

New flight test maneuvers and analysis techniques for evaluating the dynamic response of in-flight thrust models during throttle transients have been developed and validated. The approach is based on the aircraft and engine performance relationship between thrust and drag. Two flight test maneuvers, a throttle step and a throttle frequency sweep, were developed and used in the study. Graphical ...

Field hockey is a game played with a ball and stick. In this game players attempt to score goals by hitting, pushing or flicking the ball with hockey sticks into the opposing team's goal. In field hockey the penalty corner was introduced for offences by defenders in the circle. In recent years, the innovation of drag flick becomes a vital part of teams attacking arsenal due to goal scoring oppo...

Differential solar heating can result from shading by rooted emergent aquatic plants, producing a temperature difference between vegetated and unvegetated regions of a surface water body. This temperature difference will promote an exchange flow between the vegetation and open water. Drag associated with the submerged portion of the plants modifies this exchange, specifically, changing the domi...

Flow separation at the vehicle’s rear end is the major cause of an aerodynamic drag in a car. In order to delay the flow separation at the rear, bump-shaped vortex generators at the roof end of a car are tested in this paper for two different types of car models Sedan and Hatchback. The aerodynamic analysis is carried out using GAMBIT and FLUENT for Sedan and Hatchback models. Vortex Generators...

Spinal cord injury (SCI) can lead to changes in muscle activation patterns and atrophy of affected muscles. Moderate levels of SCI are typically associated with foot drag during the swing phase of locomotion. Foot drag is often used to assess locomotor recovery, but the causes remain unclear. We hypothesized that foot drag results from inappropriate muscle coordination preventing flexion at the...

Computational Fluid Dynamics (CFD) simulations were performed to predict the interference drag produced by two streamlined struts intersecting at various angles in transonic flow since no relevant experimental data are available for use in design studies. The one-equation Spalart-Allmaras turbulence model was employed in a RANS formulation assuming fully-turbulent flow. Selected cases were run ...

We show by computational solution of the incompressible Navier-Stokes equations with friction force boundary conditions, that the classical inviscid circulation theory by Kutta-Zhukovsky for lift of a wing and laminar viscous boundary layer theory by Prandtl for drag, which have dominated 20th century flight mechanics, do not correctly describe the real turbulent airflow around a wing. We show ...

The forcibly launched spores of ascomycete fungi must eject through several millimeters of nearly still air surrounding fruiting bodies to reach dispersive air flows. Because of their microscopic size, spores experience great fluid drag, and although this drag can aid transport by slowing sedimentation out of dispersive air flows, it also causes spores to decelerate rapidly after launch. We hyp...