bluff body

bluff body

[¦bləf ¦bäd·ē]
(aerospace engineering)
A body having a broad, flattened front, as in some reentry vehicles.
References in periodicals archive ?
The work presented here uses force and pressure measurements to investigate the usefulness of ventilated rear geometries on a 1/4 scale automotive bluff body.
From previous work [17] it has been seen that the k-[omega] Shear Stress Transport (SST) model [18] as RANS model and the dynamic Smagorinsky sub-grid model [19] is the preferred choice for bluff body simulations, and has therefore also been used in this study.
While the measurement principle of the SwirlMaster is based on concentric swirls that create pressure fluctuations in the medium, the VortexMaster works according to the Karman vortex principle with turbulences generated by a bluff body.
The sensor is based upon the vortex flow measurement principle, which uses a bluff body in the flow path to create small eddy currents (vortices) and the pressure of this current is measured to determine the flow through a given cross sectional area.
The devices use a bluff body obstruction to produce vortices, and an electronic transducer measures these oscillations to provide a signal proportional to flow rate.
In the case of the golf ball, which is a so-called bluff body in aerodynamic parlance, the form or pressure drag component dominates.
The problem encountered is somewhat different from the classical bluff body flow in which the bluff body is stationary.
At the latter half of the 19th century and the beginning of the 20th, researchers such as John Strutt (Lord Rayleigh) and Theodore von Karmain discovered that strings in a wind move perpendicular to the flow of air, and that vortices trail behind a bluff body in a regular pattern.
In a vortex meter, the bluff body is a piece of material with a broad, flat front that is mounted at right angles to the flowstream.
After presenting the physical aspects of the motion of a viscous fluid and the method of eigenfunction expansions, he presents sections on steady planar flows, steady three-dimensional flows, and unsteady flows, concluding with a section on external flows that includes chapters on external flows past bodies, planar bluff body flows at low Reynolds numbers, and low Reynolds number flows past streamlined bodies.
As the fluid strikes a bluff body, imparting alternating vortices downstream of the bluff, it creates a vibration on a sensor body containing a piezoelectric crystal.
As a result, the multitude of bluff body components which form the axle and wheel assemblies obstruct low momentum flow only.