Improving vortex tube performance based on vortex generator design (original) (raw)
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Vortex tube is a device which is capable of separating hot and cold gas stream form an inlet gas stream with a proper pressure .Separating cold and hot streams by using vortex tube can be used in industrial applications such as cooling equipment and refrigerators. This device suits for these applications because its light ,simple and more importantly it is compact. Many researches have been carried out in order to identify the factor which affects Vortex tube performance .Here ,an experimental study has been conducted to determine the effect of geometrical parameters on vortex tube performance and air also used as a working fluid .To achieve the maximum proficiency of a vortex tube ,form the data which obtained experimentally , optimum values for cold orifice diameter to the VT inlet diameter (d / D) and the length of VT to its inlet diameter (L/ D) for this experiment proposed.
Fabrication and Optimization of Performance of Vortex Tube Parameters
The vortex tube is a very simple device which separates a compressed gas into a cold and a hot stream. The compressed gas is injected tangentially into the tube inlet by means of nozzles. The gas develops the swirling motion into the tube. The gas leaving the tube near the wall will be warmer and that leaving the tube from the center will be cooler. The general motivation of this paper is to clarify the numerous assumptions on the vortex tube, its effect by the analysis of new measurements. The paper gives complete results with reference to performance parameters of vortex tube. The performance analysis of vortex tube having different geometrical entities is studied such as: 1. By changing the number of nozzles in the vortex tube. 2. Using Tangential Inlet. 3. Effect of these design parameters on hot and cold end is being experimented.
PERFORMANCE OF VORTEX TUBE ON VARIOUS GEOMETRIC PARAMETERS
International Journal of Mechanical and Production Engineering Research and Development (IJMPERD), 2020
This paper explains approximately the vortex tube performance based on various geometric parameters inclusive of strain, nature of gas, L/D ratio and boundless mass fractions. The cold end temperature drop was examined as the parameter to be discussed. Inlet pressure varied with an increment of 1 bar from 3 to 5 bars along with that the cold mass fraction also varied from 20% to 90%. Maximum cold mass fraction was obtained at 60%. Maximum cold mass fraction was obtained at L/D ratio at 17.5 and at pressure 4 bar. While experimenting the various components like air, carbon-dioxide and nitrogen gases, the maximum cold mass fraction has been obtained for Co2 gas at L/D ratio at 17.5.Maximum temperature gradient occurred at 700 KPa inlet pressure in case of air, nitrogen, oxygen and argon etc. Maximum temperature difference was obtained for argon at 52.1ᵒ C. Temperature gradient decreases with increase in nozzle number. Maximum temperature difference was obtained at nozzle number equals to 2. Finally it has been found that the performance of vortex tube varies due to the level of temperature at different parameters.
An experimental investigation of the optimum geometry for the cold end orifice of a vortex tube
Applied Thermal Engineering, 2009
A vortex tube is a simple mechanical device, which splits a compressed gas stream into a cold and hot stream without any chemical reactions or external energy supply. This paper presents the results of a series of experiments focusing on various geometries of the ''cold end side" for different inlet pressures and cold fractions. Specifically, the tests were conducted using different cold end orifice diameters. Energy separation and energy flux separation efficiencies are defined and used to recover characteristic properties of the vortex tube. These are used to show an appropriate scale to non-dimensionalize the energy separation effect. The experimental results indicate that there is an optimum diameter of cold end orifice for achieving maximum energy separation. The results also show that the maximum value of energy separation was always reachable at a 60% cold fraction irrespective of the orifice diameter and the inlet pressure. The results are compared with the previous studies on internal flow structure, and optimal operating parameters are shown to be consistent with a matching of orifice size with the secondary circulation being observed.
Modification and experimental research on vortex tube
International Journal of Refrigeration, 2007
Vortex tube (VT) is a simple energy separating device which is compact and simple to produce and to operate. Although intensive research has been carried out in many countries over the years, the efficiency is still low. In order to improve the energy separate efficiency of vortex tubes, three innovative technologies were applied to vortex tubes. A new nozzle with equal gradient of Mach number and a new intake flow passage of nozzles with equal flow velocity were designed and developed to reduce the flow loss. A new kind of diffuser invented by us was installed for reducing friction loss of air flow energy at the end of the hot end tube of vortex tube, which can greatly improve the performance of vortex tube. The experiment results indicated that these modifications could remarkably improve the performance of vortex tube. The developed vortex tube was not only superior to the conventional vortex tube but also superior to that made by two companies in world under big cold gas mass flow ratio.
Simulation of vortex tube using natural gas as working fluid with application in city gas stations
2016
The work has been done on a 3D model of vortex tube and the governing equations have been solved using ANSYS– FLUENTTM software. Simulations were performed using density based solver and k-ε turbulence model. After validating some results of present study with available data, the effects of geometrical parameters and air/natural gas flow in a vortex tube with 6 and 2 tangential nozzles was examined. The performance of vortex tube with 6 nozzles was better when compared with 2 nozzles which is in satisfactory agreement with previous experiments, so we only show the results for the 6 nozzles vortex tube. There is a little difference between air and natural gas as a working fluid. We found that the temperature difference between hot and cold ends for air flow was little more than natural gas. Based on the results obtained in this work it is concluded that vortex process based on pressurized natural gas can be used in C.G.S as a heat exchanger for high efficiency operation and energy sa...
Comparative Study of Conventional Vortex Tube and Modified Vortex Tube
Vortex tube (VT) is a simple energy separating device which is compact and simple to produce and to operate. Although intensive research has been carried out in many countries over the years, the efficiency is still low. In order to improve the energy separate efficiency of vortex tubes, three innovative technologies were applied to vortex tubes. A new nozzle with equal gradient of Mach number and a new intake flow passage of nozzles with equal flow velocity were designed and developed to reduce the flow loss. A new kind of diffuser invented by us was installed for reducing friction loss of air flow energy at the end of the hot end tube of vortex tube, which can greatly improve the performance of vortex tube. The experiment results indicated that these modifications could remarkably improve the performance of vortex tube. The developed vortex tube was not only superior to the conventional vortex tube but also superior to that made by two companies in world under big cold gas mass flow ratio.
EXPERIMENTAL PERFORMANCE ANALYSIS OF VORTEX TUBE FOR VARIOUS PARAMETERS
The vortex tube (also called the Ranque-Hilsch vortex tube) is a mechanical device containing an entrance of nozzle with a central orifice, a vortex tube and a cone-shaped valve. A source of compressed gas (e.g. air) at high pressure enters the vortex tube tangentially through the inlet nozzle at high velocity. The expanding air inside the tube creates a rapidly spinning vortex. Once this vortex is set up in the tube, the air near the axis cools down while the air at periphery heats up in comparison with the inlet temperature. This phenomenon is known as temperature separation effect (also called the Ranque-Hilsch effect).In this study, three Ranque-Hilsch vortex tubes were used, which have 26.4 mm, 21.2mm, and 14.8 mm inside diameter and length/diameter ratio was 20, 30, and 40respectively. Their performances were examined as one of the classical RHVT and other was cold cascade type RHVT. Performance analysis was according to temperature difference between the inlet and the cold outlet (∆Tcold). The ∆Tcold values of cold cascade type Ranque-Hilsch vortex tubes were greater than the ∆Tcold values of classical RHVT, which were determined experimentally. The total inlet energy, total outlet energy, total lost energy and energy efficiency of cold stream were investigated by using experimental data. In both the classical RHVT and cold cascade type RHVT, it was found that as fraction of cold flow increases the total energy increases. It was also found that, the cold cascade type RHVT more energy efficiency of cold outlet than the classical RHVT. Excess ∆Tcold value of cold cascade type Ranque-Hilsch vortex tube causes the excess energy efficiency of cold outlet. The range of operating conditions covered; Pressure:-5 bar to 7 bar; cold fraction:-0.2to 1. In order to investigate the effect of materials, vortex tubes of steel, aluminium and PVC are fabricated and tested.
Experimental analysis of vortex tube by varying the geometry and material a review
Refrigeration plays an important role in developing countries, primarily for the preservation of food, medicine, and for air conditioning Conventional refrigeration systems are using Freon as refrigerant. As they are the main cause for depleting ozone layer, extensive research work is going on alternate refrigeration systems. Vortex tube (VT) is a non-conventional cooling device, having no moving parts which are capable of separating hot and cold gas stream form an inlet gas stream with a proper pressure without affecting the environment. This device suits for vital applications because of its light weight, simple and more importantly it is compact. This paper presents experimental results by the different investigators on the effect of various geometrical parameters, like nozzles, orifice, conical needle modifications, and different material like metallic and non metallic and experiment, to improve cop, cooling performance of vortex tube under these conditions listed below. 1. Tangential nozzle orientation with Symmetry/ asymmetry of around 4 nozzles with stopper. (dc= 14, 12,10,8, and 6mm), with constant nozzle diameter of 6.5 mm by varying the pressure of the inlet air 2-6 bar 5. The effects of cooling of a hot tube directly cooled by cooling water jacket. 6. The effect of cold end side which has the form of convergent helical nozzles with 7 mm orifice diameter and 6 no. of nozzles by inlet pressure (2 to 5 bar in step of 1bar ),conical valves with an angle . 7. The effect of Ranque-Hilsch vortex tube (RHVT) with threads cut (pitch is 1 and 2 mm) on its inner surface of hot tube. 8. Different materials of hot tubes with adiabatic like Mild steel, Aluminium and Copper with same L/D ratio 9. By influence of uniform curvature of main tube of VT Also by the literature review it is clear that there is no theory so perfect, which gives the satisfactory explanation of the vortex tube phenomenon. Due to this reason researcher conduct the series of experimentation to understand the effect of various parameters mentioned above to improve the performance of vortex tube.
Development of Two Opposing Nozzle Vortex Tube Using Air as Working Fluid
One of the practical applications of thermodynamics is refrigeration where heat is transferred from low temperature region to high temperature region through the working fluid known as refrigerant. Vapour compression and vapour absorption refrigeration systems are two commonly employed conventional systems in almost all the major applications of refrigeration and air-conditioning. The chronological literature review describes the past studies on the various issues of vortex tubes including theory, operation and design. The performance of vortex tube depends on various geometric parameters, operating parameters and gaseous properties. The magnitude of the energy separation increases as the length of the vortex tube increases to a critical length. However, a further increase of the vortex tube length beyond the critical length does not improve the energy separation. A very small diameter vortex tube leads to low diffusion of kinetic energy which also means low temperature separation. A very large tube diameter would result in lower overall tangential velocities both in the core and in the periphery region that would produce low diffusion of mean kinetic energy and also low temperature. There must be an optimum value of cold orifice diameter so that we get desired performance of vortex tube.