Aortic valve resistance has been proposed to represent the severity of aortic stenosis because some studies observed that it was less affected by change in flow than the valve-effective orifice area, but this issue remains controversial. The objective of this study was to systematically analyze the theoretical and practical determinants of these parameters in relation to changes in flow. Valve ...

We report on numerical solutions of the Gross-Pitaevskii equation for two-dimensional flow of a superfluid condensate through a small orifice. Above a critical velocity of about 30% of the speed of sound, cavitation occurs in the throat of the orifice. The cavitating bubbles form the cores of singly quantized vortices which detach from the boundary and are convected downstream.

R eduction of nonrevenue water use is currently a common goal for most water distribution systems. Nonrevenue water consists of water lost either through real losses (e.g., underground leakage) or through apparent losses (e.g., metering inaccuracies and unauthorized use). Reducing the apparent losses caused by meter inaccuracies at low flows can result in substantial short-term increases in uti...

OBJECTIVE The hemodynamics in proximity to stented aortic bioprostheses still differ from that under physiological conditions. This may prevent desired cardiac remodeling and promote aortic diseases. Further improvements in prosthetic technology require an accurate survey of the flow conditions on the prosthetic level and in the ascending aorta. Cardiovascular magnetic resonance (CMR) may have ...

The flow field development through a simplified shock absorber orifice geometry is investigated using single phase Large Eddy Simulation. Hydraulic oil used as the working fluid with constant inlet velocity and an open top boundary to allow study focus on free shear layer in vicinity of main orifice. validated standard mixing dynamics. impact shape discussed regards initial growth, potential ap...

This paper deals with some problems of measurement error analysis for flow measurement by electromagnetic flow meter. Two main groups of errors are discussed. The first group of errors is caused by various flow parameters which differ from the flow characteristics during calibration. The authors present a new method of errors estimating, called the moving stream method that allows to estimate o...

Early detection and accurate estimation of COA severity are the most important predictors of successful long-term outcome. However, current clinical parameters used for the evaluation of the severity of COA have several limitations and are flow dependent. The objectives of this study are to evaluate the limitations of current existing parameters for the evaluation of the severity of coarctation...

As a successive alkalinity-producing system pond for purifying mine drainage is operated, sediment accumulates in the limestone layer of pond, and as amount accumulated increases, water permeability treatment efficiency decrease. Hence, flushing required, comprising network perforated pipes installed layers, to periodically discharge outside. The performance depends on four distinct characteris...