3D CFD Exergy Analysis of the Performance of a Counter Flow Vortex Tube

3D CFD Exergy Analysis of the Performance of a Counter Flow Vortex Tube

S.E. Rafiee*  M.M. Sadeghiazad

Department of Mechanical Engineering, Urmia University of Technology, Urmia, Iran.

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31 December 2014
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In this numerical study, exergy analysis of a Ranque-Hilsch vortex twbe (RHVT) has been investigated. The threedimensional ( $3 \mathrm{D}$ ) computational fluid dynamic (CFD) model which is used in this study is a steady axisymmetric model that employs two turbulence models (standard k- $\varepsilon$ and standard $k$ - $-\omega$ ) to perform the computation procedure of results. All of these computations are based on the second-order numerical schemes. The curves of exergy performance such as inlet exergy, exergy of cold and hot outlet, lost exergy and exergy efficiency have been achieved for the present vortex tube. These curves have been validated with the experimental data and have shown good agreement. In this paper, variation of exergy in the cold and hot exit has been predicted as a function of cold mass fraction and the behaviors of obtained curves have been discussed. In addition, variation of temperature and pressure in the cold and hot exhaust has been presented as a function of cold mass fraction. More ever the comparison between two turbulence model results has been obtained in different fields such as exergy, pressure and temperature.


exergy analysis, ranque-hilsch vortex tube (RHVT), three-dimensional (3D), computational fluid dynamic (CFD) model, turbulence models

1. Introduction
2. Turbulence Model Description
3. Physical and 3D CFD Model of Vortex Tube
4. Results and Discussion
5. Conclusions

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