This article describes the energy separation with the simulation of a three dimensional flow field in Ranque-Hilsch vortex tube. Rectangular and trapezoidal shaped inlets with varying aspect ratio are compared and analyzed while other geometrical parameters are held constant. Air is used as a working fluid. The nature of flow field inside the vortex tube is observed for different cases at an inlet pressure condition of 6 bar (absolute). From the results, it is observed that inlet with higher aspect ratio gives higher temperature separation. The trapezoidal inlet configuration is found to give higher temperature separation as compared to a rectangular shape. The streamlines emanating at the hot and cold end exits for both the rectangular and trapezoidal are visualized. Residence time for two shapes is calculated and found to be higher for trapezoidal shape. The increase in turbulence kinetic energy for the cold end exiting streamlines at the dividing region between core and periphery could be an important factor towards energy separation. © 2016 Elsevier Ltd.

Manimaran R

Mechanical

School of Mechanical Engineering

Chennai Campus

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

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VIT University

Energy

In the last decades, the theory of energy separation in vortex tubes is debated broadly based on the heat transfer and work transfer between core and peripheral flow layers. Many parameters were considered in the literature. However, the present study involves the inlet energy considered collectively towards energy separation. In this paper, three-dimensional computational fluid dynamic simulations are discussed in vortex tube to analyze the energy separation phenomena in different cases by varying the working medium such as hydrogen and air having specific heat variation. The energy at the inlet is maintained same in both cases by adjusting the inlet mass flow rate. The results from this study are validated with recently published literature using hydrogen as a working medium. Vortex tube with hydrogen as working medium yields a temperature separation of 8 K lower than air as working medium. Further studies on vortex tube with hydrogen as a working fluid is explored at different inlet temperatures relative to the room temperature. Vortex tube with hydrogen at an inlet temperature of 400 K gives better temperature separation as compared to other inlet temperatures considered in this study. © 2019 Hydrogen Energy Publications LLC

International Journal of Hydrogen Energy

Numerical investigations on flow characteristics and energy separation in a Ranque Hilsch vortex tube with hydrogen as working medium

In the present study, three dimensional computational fluid dynamic simulations are carried out to understand the energy separation in the counter-flow vortex tube. The objective of the work is to understand the flow features that affect the energy separation between the core and peripheral flow layers inside the vortex tube. Trapezoidal shaped inlets of varying numbers from one to six are compared and analyzed, while the total inlet mass flow rate and other geometrical parameters are held constant with air as a working fluid. From the results, highest temperature separation is observed with single inlet as observed in the literature. Further, the vorticity and turbulent kinetic energy at the dividing line between core and periphery decrease with the increase in number of inlets. To understand the same, streamlines are visualized. Analysis reveals that higher core flow layer diameter, lower mean pitch distance and longer residence time are the main factors affecting energy separation. It is also found that secondary circulation vortices are prominent with the single inlet. The size of these vortices regardless of the number plays a key role in energy separation. © 2017 Elsevier Ltd

Computational analysis of flow features and energy separation in a counter-flow vortex tube based on number of inlets

Computational analysis of energy separation in counter—flow vortex tube

Computational investigation of different effects on the performance of the Ranque–Hilsch vortex tube

Improving vortex tube performance based on vortex generator design

An experimental study of a counter-flow Ranque-Hilsch vortex tube is reported here. Literature has been divided over the mechanism of energy transfer responsible for the temperature separation in the vortex tube. A black box approach is used to design experiments to infer the relative roles of heat transfer and shear work transfer in the counter-flow vortex tube. To this end, the stagnation temperature and the mass flow rates are measured at the inlet and the two outlets. In addition, pressure measurements at the stagnation condition and at the inlet section to the vortex tube were made. Based on these experiments, it is reasoned that the predominant mode of energy transfer responsible for temperature separation in a counter-flow vortex is the shear work transfer between the core and the periphery. Copyright © 2014 by ASME.

Journal of Heat Transfer

Experimental investigation of temperature separation in a counter-flow vortex tube

Experimental study and three-dimensional (3D) computational fluid dynamics (CFD) analysis on the effect of the convergence ratio, pressure inlet and number of nozzle intake on vortex tube performance–Validation and CFD optimization

Journal	Data powered by TypesetEnergy
Publisher	Data powered by TypesetElsevier BV
ISSN	0360-5442
Open Access	0