The incidence of recurrent pneumothoraces was analyzed in mechanically ventilated patients with the adult respiratory distress syndrome (ARDS) or non-ARDS causes of respiratory failure who had ipsilateral chest tubes in place. The radiographs of 39 consecutive patients with 47 initial pneumothoraces were evaluated for pneumothorax recurrence and chest tube positioning, which was prospectively d...

This study investigates the pool boiling heat transfer of water over cylindrical heating tubes for different orientations and surface roughness tubes. First, two a smooth tube, horizontal vertical, were used in chamber. For given flux, coefficient achieved with tube was always higher than that vertical tube. To investigate influence roughness, rough fully outer developed through metal etching p...

the pressure drop of refrigerant r-134a flow boiling inside a horizontal tube has been investigated experimentally. the test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. these instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. this system consisted of three electrically heated evapor...

natural convection heat transfer from a tube bundle in the indirect water bath heaters is investigated. a computer-code is used for the solution of the governing equations of mass, momentum and energy transfer based on the simple-c algorithm. simulations are carried out for the gas pressure station heater of kermanshah city with various tube bundle arrangements. in order to validate the numeric...

BACKGROUND One of the most effective ways for distal movement of molars to treat Class II malocclusion is using extraoral force through a headgear device. The purpose of this study was the comparison of stress distribution in maxillary first molar periodontium using straight pull headgear in vertical and horizontal tubes through finite element method. MATERIALS AND METHODS Based on the real g...

Abstract   An empirical investigation was carried out to study convective heat transfer of nanofluid flow inside an inclined copper tube under uniform heat flux condition. Required data are acquired for laminar and hydrodynamically fully developed flow inside round tube. The stable CuO-base oil nanofluid with different nanoparticle weight fractions of 0.5%, 1% and 2% was produced by means of ul...

An experimental investigation on heat transfer coefficient is presented from three horizontal tubes in a vertical array in a duct for 500<ReD<6000. A mass transfer measuring technique based on psychrometry chart is used to determine heat transfer coefficient. The diameter of the tubes is 11 mm each spaced 40 mm apart and in-line pitch ratio varies &#10in the range 0.055<D/W<0.22. The experimen...

An experimental investigation on heat transfer coefficient is presented from three horizontal tubes in a vertical array in a duct for 500<ReD<6000. A mass transfer measuring technique based on psychrometry chart is used to determine heat transfer coefficient. The diameter of the tubes is 11 mm each spaced 40 mm apart and in-line pitch ratio varies in the range 0.055<D/W<0.22. The experimenta...

BACKGROUND Recent data suggest that during mechanical ventilation the lateral-horizontal patient position (in which the endotracheal tube is horizontal) decreases the risk of ventilator-associated pneumonia, compared to the recommended semi-recumbent position (in which the endotracheal tube slopes downward into the trachea). We tested the feasibility of the lateral-horizontal patient position, ...