Peak flow meters are essential tools in the management of asthma. Many types are on the market. A computer-driven piston pump is normally not available for evaluation of the various meters. Comparison with values from a pneumotachograph is an accepted way of testing peak flow meters. This study aims at comparing 11 peak flow meters, for accuracy and linearity. Seven adult peak flow meters were ...

This work aims to present a numerical analysis of the natural gas which flows through a high-pressure pipeline and an orifice plate, through the use of CFD methods. The paper contains CFD calculations for the flow of natural gas in a pipe with different geometry used for the orifice plates. One of them has a standard geometry and a shape without any deformation and the other is deformed by the ...

Side-type orifice intake is a type of selective withdrawal facility used in managing reservoirs to mitigate the negative effects of low-temperature water. Based on the temperature data of a thermal stratified reservoir in China, an experiment was conducted in flume to study the influence of intake flow rate on withdrawn water temperature with different temperature distributions. Results indicat...

Closed cycle He sorption refrigerators are an increasingly popular choice for remote cryogenic operations. The presence of a superfluid film on the inner walls of the evaporation pot limits their performance. We present a simple model of the gas, film, and heat flow in a He sorption refrigerator, taking into account the effects of an orifice to limit superfluid film flow. The model serves as a ...

A comparison has been made of the new peak flow gauge and the Wright peak flow meter. Close correlation was found between measurements made with the two instruments both in normal subjects and in patients. The peak flow gauge is as consistent as the peak flow meter but is cheaper and more portable. It should be useful in survey work in general practice and for loan from hospital outpatient depa...

Pulsed wave Doppler estimates of blood flow velocity were made across the mitral, tricuspid, aortic, and pulmonary valves in a series of 120 normal fetuses (gestational age 16-36 weeks). In 36 of these the data were obtained in all four sites. The maximum and mean velocities were calculated for each valve and these values were plotted against gestational age. There was little change in these va...

OBJECTIVE To better understand the mechanism of stroke during cardiopulmonary bypass, it is necessary to obtain information on the location of turbulence, wall pressure, and flow distribution within the aortic arch. METHODS Blood flow was numerically simulated using the finite element method in the following representative case: a curved arterial cannula was inserted into the anterior wall of...