The objectives in this thesis are to present a model of a variable venturi in an exhaust gas recirculation (EGR) system located in a heavy duty diesel engine. A new legislation called EURO 4 will come into force in 2005 which affects truck development and it will require an On-Board Diagnostic system in the truck. If model based diagnostic systems are to be used, one of the advantages is that t...

The objectives in this thesis are to present a model of a variable venturi in an exhaust gas recirculation (EGR) system located in a heavy duty diesel engine. A new legislation called EURO 4 will come into force in 2005 which affects truck development and it will require an On-Board Diagnostic system in the truck. If model based diagnostic systems are to be used, one of the advantages is that t...

INTRODUCTION In immunocompromised patients, acute respiratory failure (ARF) is associated with high mortality, particularly when invasive mechanical ventilation (IMV) is required. In patients with severe hypoxemia, high-flow nasal oxygen (HFNO) therapy has been used as an alternative to delivery of oxygen via a Venturi mask. Our objective in the present study was to compare HFNO and Venturi mas...

A proximal positive end-expiratory pressure (PEEP) and continuous positive airway pressure (CPAP) system was constructed by the simple addition of a venturi T-piece proximal to the exhalation limb of a breathing circuit. The level of PEEP or CPAP was determined by the amount of flow powering the venturi. This system can provide positive pressure in excess of 40 cm H2O without the need for check...

Particle collection efficiencies in 23 size intervals covering a diameter range of 0.32-2.8 pm were measured for venturi scrubbers with throat diameters of 3.2,5.4, and 7.6 cm. Each scrubber was operated with four types of liquid injection, throat gas velocities from 21 to 160 m/s, and liquid-to-gas volume ratios from 0.000 19 to 0.0043. Results were compared to three widely used theoretical mo...

BACKGROUND A table of the approximate ranges of inspired oxygen delivered at given oxygen flow rates is often given on the packaging of oxygen masks. A study was carried out to check the inspired oxygen concentration given by one of the new masks, which has been designed to be used with or without the Venturi attachment as a result of the proposal to use it without the Venturi attachment as a g...

A Venturi scrubber has dispersed three-phase flow of gas, dust, and liquid. Atomization of a liquid jet and interaction between the phases has a large effect on the performance of Venturi scrubbers. In this study, a computational model for the interactive three-phase flow in a Venturi scrubber has been developed to estimate pressure drop and collection efficiency. The Eulerian-Lagrangian method...

Annular gas-liquid two phase flow is widely encountered in the nuclear industry. Various combinations of techniques have been employed in annular gas-liquid two phase flows to measure the flow parameters (e.g. liquid film thickness, gas volume fraction and the phase flow rates). One of the most useful techniques which has proven attractive for many multiphase flow applications is the electrical...

Attempts to improve drug delivery from conventional jet nebulizers have included the use of storage systems to reduce drug wastage during exhalation. Venturi nebulizers enhance drug delivery during inhalation, reducing treatment times and drug wastage. This study investigated the effect of age on inhaled dose from a conventional jet nebulizer (Acorn) used both with and without a storage chamber...

The development and illustrative applications of an ambient ionization technique termed Venturi easy ambient sonic-spray ionization (V-EASI) is described. Its dual mode of operation with Venturi self-pumping makes V-EASI applicable to the direct mass spectrometric analysis of both liquid (V(L)-EASI) and solid (V(S)-EASI) samples. V-EASI is simple and easy to assemble, operating solely via the a...