Some falcons, such as peregrines (Falco peregrinus), attack their prey in the air at the end of high-speed dives and are thought to be the fastest of animals. Estimates of their top speed in a dive range up to 157 m s-1, although speeds this high have never been accurately measured. This study investigates the aerodynamic and gravitational forces on 'ideal falcons' and uses a mathematical model...

Flight is one of the energetically most costly activities in the animal kingdom, suggesting that natural selection should work to optimize flight performance. The similar size and flight speed of birds and bats may therefore suggest convergent aerodynamic performance; alternatively, flight performance could be restricted by phylogenetic constraints. We test which of these scenarios fit to two m...

in this research, modeling of limiting flux in membrane filtration of skimmed milk as well as the results of simulation by matlab is presented. the presented model is actually a force balance approach and consists of drag, gravitational and lift forces, and forces between colloidal particles (electrostatic repulsive and van der waals attractive forces). to consider the back diffusion phenomenon...

electric vehicles (evs) have gained the attention of many authorities, automakers and researchers due to their considerable energy saving and emission reduction. one of the main issues that must be considered in design of a road vehicle is the calculation of aerodynamic forces. this issue also must be scrutinized in the design of evs. installation of rear spoiler is one of the solutions propose...

The measurement of aerodynamic forces and moments acting on an aircraft model is important for the development of wind tunnel measurement technology to predict the performance of the full scale vehicle. The potentials of an aircraft model with and without winglet and aerodynamic characteristics with NACA wing No. 65-3218 have been studied using subsonic wind tunnel of 1 m × 1 m rectangular test...

A small flying machine based upon a new mechanism was realized. The flying machine driven by magnetic torque had hard magnetic rims as wings and a soft magnetic wire as a body, respectively. The wing has two hinges, which create different drag during up and down strokes, and produced lifting force. Shape magnetic anisotropy of the body stabilized the attitude, The flying machine flew without po...

The Breguet range equation indicates that to the first order of approximation range will be maximized by maximizing ML/D, where M is the Mach number and L/D is the lift/drag ratio. Since the drag coefficient increases very rapidly as the Mach number approaches one, this leads to the design of a long range aircraft which fly at high subsonic speeds, typically in the range Mach 0.8 to 0.85, just ...