There are different methods to reduce drag in high speed hulls. One of these methods is a change in the shape of the body by adding longitudinal side tunnels. In this paper it has been attempted to determine the influence of the tunnel height on hydrodynamic characteristics of the hull to achieving an optimum shape for the tunnel. To achieve this purpose, numerical simulation of the problem has...

Active flow control with jet devices is a promising approach for vehicle aerodynamics control. In this work an extended computational study performed comparing three different actuation strategies active around the square back Ahmed body at Reynolds number 500,000 (based on height). Numerical simulations are run using Large Eddy Simulation (LES) approach, well adapted to calculate unsteady high...

This article gives the perturbative NNLO results for the moments of the most commonly used event shape variables associated to three-jet events in electron-positron annihilation: Thrust, heavy jet mass, wide jet broadening, total jet broadening, C parameter and the Durham three-to-two jet transition variable.

Oxygen consumption (VO2) during surface swimming and total body drag were investigated in the North American mink, Mustela vision Schreber. Over the range of 0.13-0.70 ms-1, VO2 increased curvilinearly with speed for minks swimming against a current in a water flume. Similarly, body drag of a mink carcass increased non-linearly with speed and was described by the equation, Drag = 1.24 velocity....

In Taylor-Couette flow the total energy dissipation rate and therefore the drag can be determined by measuring the torque on the system. We do so for Reynolds numbers between Re=7 x 10(4) and Re=10(6) after having injected (i) small bubbles (R=1 mm) up to a volume concentration of alpha=5% and (ii) buoyant particles (rhop/rhol=0.14) of comparable volume concentration. In case (i) we observe a c...

In team pursuit, the drag of a group of cyclists riding in a pace line is dependent on several factors, such as anthropometric characteristics (stature) and position of each cyclist as well as the sequence in which they ride. To increase insight in drag reduction mechanisms, the aerodynamic drag of four cyclists riding in a pace line was investigated, using four different cyclists, and for four...

This article gives the perturbative NNLO results for the most commonly used event shape variables associated to three-jet events in electron-positron annihilation: Thrust, heavy jet mass, wide jet broadening, total jet broadening, C parameter and the Durham three-to-two jet transition variable. In addition the NNLO results for the jet rates corresponding to the Durham, Geneva, Jade-E0 and Cambr...

Aerodynamic drag is an important factor in vehicles fuel consumption. Pressure drag which is the main component of total drag is a result of boundary layer separation from vehicle surface. Flow control methods are applied to avoid or at least delay separation. Depending upon whether these methods consume energy to control the flow or not, they are called active or passive control methods. In th...

Simulation of an underwater glider to investigate the effect of angle of attack on the hydrodynamic coefficients such as lift, drag, and torque. Due to the vital role of these coefficients in designing the controllers of a glider and to obtain an accurate result, this simulation has been studied at a range of operating velocities. The total length of the underwater glider with two wings is 900 ...