The problem of Reynolds-averaged modeling turbulent boundary-layer flow over surfaces arbitrary roughness is studied using the results direct numerical simulations many different rough surfaces. complexity in sublayer such that most effective general strategy appears to be model it as a prescribed velocity profile, either at coarse level conventional roughness-specific log-linear wall function,...

1. Abstract The main purpose of this paper is to describe a numerical method of an inverse problem for two– dimensional flow of fluid around a profile. The principle of the method is based on construction of a contractive operator. The practical use is getting the possibility of constructing or modifying the shape of a profile by the velocity distribution on the profile surface. We formulate an...

A 1-D and 2-D cylindrical flow stability is investigated in this paper. A typical velocity profile in a shear layer with infection point is studied first. The fluid motion is decomposed to two parts: the rotational part and shear part. Linear stability analysis shows the rotational part (like rigid body) is stable but the shear part is unstable. Of course, the shear layer with inflection point ...

We investigate the effect of pair creation on a shock structure. Actually, particles accelerated by a shock can be sufficiently energetic to boost, via Inverse Compton (IC) process for example, surrounding soft photons above the rest mass electron energy and thus to trigger the pair creation process. The increase of the associated pair pressure is thus able to disrupt the plasma flow and possib...

⎯ The omni-directional sensitivity pattern of an integrated three dimensional acoustic sensor, composed of four hot-wire particle velocity sensors is analyzed theoretically and experimentally. We investigate the influence of the presence of the probe surface on the direction of the measured particle velocity measured by the sensors, and a description of the gas flow profile around the integrate...

The aim of this paper is to study the effect of slip velocity and shape of stenosis on non-Newtonian flow of blood through a stenosed arterial segment. Blood is modeled as Bingham-Plastic fluid in a uniform circular tube with a radially non-symmetric stenosis. The problem is investigated by a joint effort of analytical and numerical techniques. The influence of stenosis shape parameter, slip ve...

In the Manning equation the hydraulic radius can be defined as the cross-section dimension of the shape. In pipe flow the bed shear stress is assumed to be uniformly distributed along the wetted perimeter which cannot be true in open channel flow. Hence, three approximation of the true boundary shear-stress distribution are examined and more practical conveyance depth or resistance radius formu...

We studied the effects of vigorous rowing training on left ventricular structure and function using M-mode, two-dimensional and Doppler echocardiography in 10 female college rowers. Echocardiographic measurements were performed before and after 20 weeks of rowing training. Diastolic function was also estimated by measuring the isovolumetric relaxation time (IRT), deceleration time (DcT), peak v...

Radial profiles of particle velocities were investigated in a 6.1m high methanol-to-olefins cold model experimental device using a TSI laser Doppler velocimeter. The effect of axial height on flow development was not obvious in fully developed region under the same operating condition. Superficial gas velocity and solid circulating rate had significant influence on particle velocity in the cent...

background: to determine whether islamic fasting would change cerebral blood flow during ramadan. methods: the study group comprised 20 subjects (16 males and 4 females) on a regimen of 1 month food and water intake restriction, according to islamic fasting ritual. subjects were evaluated for cerebral bolo flow through a middle cerebral artery (mca) by means of transcranial doppler (tcd), the d...