Design and performance analysis of double-flux supersonic air ejector

Download

index.pdf

Date

2018

Author

Bozkır, Berk

Metadata

Show full item record

Item Usage Stats

225
views

150
downloads

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

Suggestions

OpenMETU
Core

Design and analysis of a vertical axis water turbine for river applications using computational fluid dynamics Demircan, Eren; Aksel, Mehmet Haluk; Pınarcıoğlu, Mehmet Melih; Department of Mechanical Engineering (2014) The main purpose of this study is to design a Darrieus rotor type vertical axis water turbine using Computational Fluid Dynamics (CFD) in order to be used in river currents. The CFD modeling is based on two dimensional numerical solution of the rotor motion using commercial Unsteady Reynolds Averaged Navier-Stokes solvers, Ansys Fluent and CFX. To validate the two dimensional numerical solution, an experimental Darrieus rotor type water turbine from literature is studied and performance of several turbulenc...
INVESTIGATION AND OPTIMIZATION OF WINGLETS FOR HAWT ROTOR BLADES Elfarra, Monier A.; Akmandor, I. Sinan; Sezer Uzol, Nilay (2011-03-25) The main purpose of this paper is to optimize winglet geometry by using CFD with Genetic Algorithm and study its effects on power production. For validation and as a baseline rotor, the NREL Phase VI wind turbine rotor blade is used. The Reynolds-Averaged Navier-Stokes equations are solved and different turbulence models including the Spalart-Allmaras, k-epsilon Launder-Sharma, k-epsilon Yang-Shih and SST k-omega models are used and tested. The results of the power curve and the pressure distribution at dif...
Investigation and optimization of winglets for hawt rotor blades Elfarra, Monier A.; Akmandor, I. Sinan; Sezer Uzol, Nilay (2011-01-01) The main purpose of this paper is to optimize winglet geometry by using CFD with Genetic Algorithm and study its effects on power production. For validation and as a baseline rotor, the NREL Phase VI wind turbine rotor blade is used. The Reynolds-Averaged Navier-Stokes equations are solved and different turbulence models including the Spalart-Allmaras, k-e Launder-Sharma, k-e Yang-Shih and SST k-ω models are used and tested. The results of the power curve and the pressure distribution at different spanwise ...
Application of fully implicit coupled method for 2D incompressible flows on unstructured grids Zengin, Şeyda; Tarman, Işık Hakan; Department of Engineering Sciences (2012) In the subject of Computational Fluid Dynamics (CFD), there seems to be small number of important progress in the pressure-based methods for several decades. Recent studies on the implicit coupled algorithms for pressure-based methods have brought a new insight. This method seems to provide a huge reduction in the solution times over segregated methods. Fully implicit coupled algorithm for pressure-based methods is very new subject with only few papers in literature. One of the most important work in this a...
Analytical modeling of asymmetric multi-segment rotor - bearing systems with Timoshenko beam model including gyroscopic moments Özşahin, Orkun; Özgüven, Hasan Nevzat (2014-11-01) In this study, analytical modeling and an analysis approach for asymmetric multi-segment rotor bearing systems are presented. Timoshenko beam model which includes the effect of gyroscopic moments is employed for modeling rotor segments. Instead of applying FEM, sub-segment Frequency Response Functions (FRFs) are obtained analytically, and sub-segment FRFs obtained are coupled by using receptance coupling method. Bearing properties are included into system dynamics by employing structural modification techni...

Citation Formats

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