Design and performance analysis of double-flux supersonic air ejector

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2018

Author

Bozkır, Berk

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The main purpose of this study is to design a double-flux supersonic ejector and to evaluate its performance associated with its entrainment ratio by employing Computational Fluid Dynamics methods as well as one-dimensional approach. Since the performance of the ejector systems is strongly dependent on the design, this study concentrates on maximizing the entrainment ratio by varying the corresponding angles and the lengths of the critical segments such as mixing angle, divergence angle, mixing throat length etc., while keeping the operational parameters unaltered. Numerically computed results and the one-dimensional calculations have been compared. It is found that the proper design is mandatory for achieving efficient entrainment ratios, and has prominent effect on the operation of the system. It is found that almost 20% of enhancement on entrainment performance can be obtained solely by modifying the lengths and angles of the ejector’s critical segments without changing the operating conditions. It is also deduced that during these modifications, the complex flow structure through the system, should not be disregarded for a thoroughly maximization of the performance and an efficient operation of the ejector.

Subject Keywords

Computational Fluid Dynamics., Supersonic Ejector Design., Ejector pumps., Air-engines.

URI

http://etd.lib.metu.edu.tr/upload/12622084/index.pdf
https://hdl.handle.net/11511/27280

Collections

Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

B. Bozkır, “Design and performance analysis of double-flux supersonic air ejector,” M.S. - Master of Science, Middle East Technical University, 2018.