PURPOSE To quantitatively model the changes in blood velocity profiles for different cardiac phases in human retinal vessels. METHODS An adaptive optics scanning laser ophthalmoscope (AOSLO) was used to measure blood velocity profiles in three healthy subjects. Blood velocity was measured by tracking erythrocytes moving across a scanning line. From the radial position of the cells within the ...

a theoretical solution is presented for the forced convection heat transfer of a viscoelastic fluid obeying the giesekus constitutive equation in a concentric annulus under steady state, laminar, and purely tangential flow. a relative rotational motion exists between the inner and the outer cylinders, which induces the flow. a constant temperature was set in both cylinders, in this study. the f...

Flow velocity profiles of micro counter-current flow of aqueous and butylacetate phases in a microchannel having a width of 100 microm were measured by micro particle image velocimetry. In order to analyze the hydrodynamic characteristics of the counter-current flow, we derived a simple analytical model for the velocity profile. When flow rates of the aqueous and organic phases were 0.2 and 0.1...

Instantaneous velocity of pulmonary artery blood was measured using a thin-film resistance anemometer mounted on a hypodermic needle. Studies were performed, at thoracotomy, in five dogs and five patients. Instantaneous blood velocity was recorded at several sites across die transverse axis of the main pulmonary artery to determine the shape of the velocity profile. We found the velocity profil...

− In this paper a cost-effective method for measuring transportation velocity and the velocity profile of a material flow of powdery solids inside a pipe is presented. For the measurement, artificial perturbations are brought into the mass flow and the effects of these perturbations are acquired and correlated at measurement sections. The velocity profile is calculated with the knowledge of the...

Electromagnetic flow metres based on the principles of Faraday's laws of induction have been used successfully in many industries. The conventional electromagnetic flow metre can measure the mean liquid velocity in axisymmetric single phase flows. However, in order to achieve velocity profile measurements in single phase flows with non-uniform velocity profiles, a novel imaging electromagnetic ...

Electromagnetic flow meters based on the principles of Faraday’s laws of induction have been used successfully in many industries. The conventional electromagnetic flow meter can measure the mean liquid velocity in axisymmetric single phase flows. However, in order to achieve velocity profile measurements in single phase flows with non-uniform velocity profiles, a novel Imaging Electromagnetic ...

BACKGROUND Flow-rate dependencies of the Doppler continuity equation are addressed in this study. METHODS AND RESULTS By use of computational fluid dynamic (CFD) software with turbulence modeling, three-dimensional axisymmetric models of round stenotic orifices were created. Flow simulations were run for various orifice area sizes (0.785, 1.13, 1.76, and 3.14 cm2) and flow rates (0.37 to 25.0...

An axisymmetric jet issued from a sharp edged circular convergent nozzle has been studied experimentally in the near field at Reynolds number 5.3x104  to search the saddle shape behavior of mean velocity and the role of mean static pressure in the jet flow. Due to the vena contracta effect the centerline mean velocity of the jet increases about 4.2% of its exit value and corresponding decrease ...

   An investigation is carried out on MHD stagnation point flow of water-based nanofluids in which the heat and mass transfer includes the effects of slip and convective boundary conditions. Employing the similarity variables, the governing partial differential equations including continuity, momentum, energy, and concentration have been reduced to ordinary ones and solved by using...