Experimental investigation of an ejector as a refrigerant expansion engine

The use of an ejector to improve the performance of a vapor compression refrigeration system was investigated. The ejector harnesses kinetic energy developed during the throttling process and returns it to the compressor in the form of a pressure boost. An ejector was designed taking into account the expected nonequilibrium behavior in the motive nozzle, and assuming equilibrium conditions in the other components. A standard vapor compression system using R-12 was modified to test the ejector. Included in the resulting ejector cycle was a hot gas bypass arrangement which was found to effectively control the condenser and evaporator flowrate. Hot gas bypass was used instead of a throttling valve, which would have undermined the benefit of the ejector. Experiments were conducted by running the ejector cycle at varying amounts of hot gas bypass flow. Performance results for the ejector and the overall cycle were obtained which showed that while the ejector recovered some of the kinetic energy of the expansion process, its design needed optimization. Recommendations were made for a more in-depth study of the ejector cycle.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Mechanical Engineering

Department dc:contributor.department

Mechanical Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1991

Author dc:creator

• Menegay, Peter

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-10222009-124957

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/45241