Numerical investigation of the energy separation effect and flow mechanism inside convergent, straight, and divergent double-sleeve RHVT

This paper aims to investigate fixed composition natural gases including N2, CH4 and C2H4 energy separation effect in vortex tube. Energy separation phenomena of those gases were investigated by means of three-dimensional Computational Fluid Dynamics (CFD) method. Flow fields of natural gases in fixed inlet boundary conditions were simulated. The results main factors were found that affect the energy separation with cold mass fraction being 0.7 and pressure drop ratio being 3.90. At the same time, this paper has illustrated the effects and tendencies of energy separation with gases in the tube under the same cold mass flow fraction and cold pressure ratio. The results show mixture gases total temperature difference effect is unchanged varied with the cold mass fraction; CH4% has no effect on the vortex cold end temperature separation, but varied of CH4% has an influence in total temperature and hot end separation effect; total temperature separation effect of CH4% was divided into two sections, one is0%-80%, and the other 80%-100%.

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Direct numerical simulation of energy separation effect in the near wake behind a circular cylinder

International Journal of Heat and Mass Transfer ◽

10.1016/j.ijheatmasstransfer.2017.11.133 ◽

2018 ◽

Vol 119 ◽

pp. 665-677 ◽

Cited By ~ 6

Author(s):

Andrey I. Aleksyuk ◽

Alexander N. Osiptsov

Keyword(s):

Numerical Simulation ◽

Circular Cylinder ◽

Direct Numerical Simulation ◽

Energy Separation ◽

Near Wake ◽

Separation Effect

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Experimental and Numerical Investigation on Effect of Convergent Angle and Cold Orifice Diameter on Thermal Performance of Convergent Vortex Tube

Journal of Thermal Science and Engineering Applications ◽

10.1115/1.4030639 ◽

2015 ◽

Vol 7 (4) ◽

Cited By ~ 15

Author(s):

Seyed Ehsan Rafiee ◽

M. M. Sadeghiazad ◽

Nasser Mostafavinia

Keyword(s):

Numerical Investigation ◽

Cfd Simulation ◽

Vortex Tube ◽

Orifice Diameter ◽

Energy Separation ◽

Separation Procedure ◽

Laboratory Setup ◽

Air Temperatures ◽

Invaluable Tool ◽

Air Separator

The vortex tube (VT) air separator is an invaluable tool which has the ability to separate a high-pressure fluid into the cold and hot fluid streams. The hot tube is a main part of the air separator VT which the energy separation procedure happens along this part. This research has been done to analyze the effect of the convergent angle and cold orifice diameter on the thermal efficiency of a convergent vortex tube (CVT). The CVT is linked to an air pipeline with the fixed pressure of 6.5 bar. The convergent hot tube angle is varied over the range of 1 deg to 9 deg. The consideration of the main angle effect denotes that the highest thermal ability could be achieved at β = 5 deg. The laboratory setup results show this subject that the optimization of the hot tube convergent angle elevates the cooling and heating effectiveness around 32.03% and 26.21%, respectively. Experiments denoted that both cooling capability and heating effectiveness reach the highest magnitudes when the DCold is around 9 mm. After these two stages, the optimized CVT was capable of decreasing and rising air temperatures at the cold and the hot sides up to 9.05 K (42.89%) and 10.48 K (44.74%), respectively. A computational fluid dynamics (CFD) model was employed to predict the performance of the air flow inside the CVT. The numerical investigation was done by full 3D steady-state CFD-simulation using fluent6.3.26. The results show that the agreement between computation predictions and laboratory measurements is fairly good.

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