Discharge tubes in hermetically sealed refrigeration compressors are often a source of fatigue failure which is not serviceable and necessitates the replacement of the compressor. The finite element method can be used to model the discharge tube to help prevent such failures and to reduce costs by optimizing the tube. This investigation considers techniques for modeling discharge tubes with fin...

abstract background: accumulation of secretions in the airways of patients with an endotracheal tube and mechanical ventilation will have serious consequences. one of the most common methods of airway clearance is endotracheal suctioning. in order to facilitate discharge of airway secretion resulting in promotion of gas exchange, chest physiotherapy techniques can be used at the time of expirat...

the direct conversion of methane to c2 hydrocarbons, in a quartz tube reactor enforced by a dc corona discharge, was investigated at atmospheric pressure. the process was carried out in the presence of metal oxide catalysts of mn/w/sio2, mn/w/sio2 (tetraethyl orthosilicate, teos), and mn/w/cnt (supported on carbon nanotubes). the total yield to c2 hydrocarbons in the presence of metal oxide cat...

in this study, liquid-liquid extraction process in a kuhni extraction column was modeled and simulated. a non-equilibrium dynamic model was developed for modeling liquid-liquid extraction processes based on a rate-based model. the model equations are inclusive of partial and ordinary differential equations which were discretized in column height direction. the population balance model was used ...

Beam transport in plasma channels is a transport mechanism especially suited for the transport of high current beams or beams of poor quality (e.g. large momentum spread). It is currently studied as an alternative to ballistic focusing for final transport in ion beam driven inertial fusion reactors. Plasma channels are created by a discharge in a background gas. The channels can be initiated ei...

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...

PURPOSE Prolonged air or fluid chest tube drainage may delay chest tube removal in thoracic surgery patients otherwise ready for discharge. We reviewed 20 months of experience at our institution with postoperative, outpatient chest tube management using a new portable chest tube device. DESCRIPTION From May 2003 to December 2004, 457 major thoracic procedures were performed at our institution...