Arterial blood and expired gas samples were taken from 20 patients before operation and on the first day after upper abdominal surgery. After operation the patients were studied breathing air and also breathing 35% oxygen from a venturi-type mask. Preoperative Pao2 with age was exaggerated by operation. Pao2 after operation was closely related to, and lower than, the preoperative value. The pos...

Flowmetry. Fluid-flow measurement and visualisation ................................................................................ 1 Measuring mass flow-rate ......................................................................................................................... 2 Accumulative weighting .............................................................................................

G Venturi 1 , L Zammarchi 2 3 , C Fortuna 1 , ME Remoli 1 , E Benedetti 1 , C Fiorentini 1 , M Trotta 3 , C Rizzo 4 , A Mantella 2 , G Rezza 1 , A Bartoloni 2 3 1. Department of Infectious, Parasitic and Immune-Mediate Diseases, Istituto Superiore di Sanità, Rome, Italy 2. Clinica Malattie Infettive, Dipartimento di Medicina Sperimentale e Clinica, Università Degli Studi di Firenze, Florence, I...

A transfer standard for flowmeter calibration provides traceability to a primary standard. It is typically used for most commercial calibrations because it represents an economically attractive alternative to a primary system. A set of critical flow venturi (CFV) transfer standards have been maintained in calibration at CEESI for the past 35 years. The uncertainty in mass flowrate has been esti...

A compressible, multiphase, one-fluid RANS solver has been developed to study turbulent cavitating flows. The interplay between turbulence and cavitation regarding the unsteadiness and structure of the flow is complex and not well understood. This constitutes a critical point to accurately simulate the dynamic behaviour of sheet cavities. In the present study, different formulations based on a ...

BLOOD flow in single vessels can be measured by direct methods such as rotameter, drop-flow meter, Rein-thermostromuhr, Venturi principle, electromagnetic flow meter and bubble-floAV meter. Such methods are usually characterized by great accuracy, but their applicability is considerably limited in man by the fact that the appropriate vessel must be made accessible. Blood flow in some regions wa...

The Inject Pipe Mixer (IPM) are being used as venturi injectors and can also homogenize two fluids. The entry of secondary fluid as a jet influences flow field in the device. A CFD simulation of flow through an IPM (Lshape) has been carried out using ANSYS CFX 11.0 using water as the flowing fluid to understand the flow field under turbulent flow conditions using standard k--ε model. The result...

Most cancer patients experience nausea and vomiting after surgery. Today, many methods of treatment have been developed and used for the control of such symptoms. The most important are drug therapy, relaxation, oxygen therapy and gas therapy. In addition, dexamethasone, massage therapy and using a Venturi mask have also proven effective. Due to the nature of gas consumption which leads to naus...

We present an optofluidic chip with integrated polymer interferometers for measuring both the microfluidic air pressure and flow rate. The chip contains a microfluidic circuit and optical cavities on a polymer which was defined by soft lithography. The pressure can be read out by imaging the interference patterns of the cavities. The air flow rate was then calculated from the differential press...

This paper identi es a new mechanism that can a ect the discharge coe cient of critical nozzle ows. Speci cally, vibrational relaxation e ects are demonstrated to signi cantly inuence the discharge coe cient of selected gases in critical venturi ows. This phenomenon explains why certain gases { like carbon dioxide { exhibit calibration characteristics that di er signi cantly from other gases (e...