III. Preliminary results 5 IIIa. Three-mirror quasi-optical passive compressor 6 IIIb. Optimization of the three-mirror passive compressor parameters 7 IIIc. Prototype of a passive compressor with a three-mirror resonator 10 IIId. Four-mirror quasi-optical passive compressor 14 IIIe. Prototype of a passive compressor with a four mirror resonator 15 IIIf. Diffraction gratings as active elements ...

Cavitation has been investigated in directional control valves in order to identify damage mechanisms characteristic of components o f aircraft hydraulic systems. Tests have been conducted in a representative metal spool valve and in a model three times larger. Data taken under noncavitating conditions with both valves showed that the position of the high-velocity annular jet shifts orientation...

The paper describes a project to enhance the print service for CERN. The printer infrastructure consists of over 1000 printers serving more than 5000 Unix users running on workstations of various brands as well as PCs running Linux. In addition, the infrastructure must serve more than 3000 PCs running Windows/95 and NT 4. We support a large number of printer manufacturers, including HP, QMS, Te...

The last decade has seen an increasing awareness that the manner by which a compressor meets the part load conditions of residential air conditioning is a strong dete:cninant of the a.easonal SEER of the air conditioner. The compressor can reSPond to part load needs by cycling if of the single SPeed variety, by cycling between capacity levels if of the multiSPeed variety, by use of internal cap...

This research was supported by the SPOOL project organized by CSER (Consortium for Software Engineering Research) which is funded by Bell Canada, NSERC (National Sciences and Research Council of Canada), and NRC (National Research Council of Canada). Guy St-Denis is being funded by a scholarship granted by the FCAR (Formation de Chercheurs et l’Aide à la Recherche) Fund. Abstract The aim of thi...

The dynamics of reed valves of a reciprocating compressor is tightly coupled with the dynamics of fluid inside compressor ducts. A global model of a refrigerator compressor is developed taking into account the net flow through the ducts. Results show that reed valves vibrations influence the compressor cycle and can produce noise in the high frequency range.

A new type of expander-compressor system called Cross Vane expander-compressor (CVEC) was introduced. This device replaces the expansion valve and compressor in conventional refrigeration systems to reduce the energy consumption and improve the coefficient of performance (COP) of the system. As opposed to many expander-compressor systems in the literature, whereby a separated expander is couple...

Piping vibration which is mainly caused by the torsional vibration of rotary compressor can be a major noise source of air-conditioner. Especially, the tangential vibration of rotary compressor which is due to the torsional vibration is much higher than the radial vibration or the vertical vibration of compressor. A study as to how the tangential vibration of rotary compressor is related with t...

The Axial compressor is an integrated part of a gas turbine. The central part of compressors is its blades. Blade aerodynamic has a significant effect on compressor performance. Because of the adverse pressure gradient in the compressor, any deviation in the blade profile has a significant influence on the flow field as well as the compressor performance. During the manufacturing and operation ...