US20220275977A1

US20220275977A1 - Vortex tube cooling system and method of using same

Info

Publication number: US20220275977A1
Application number: US17/629,118
Authority: US
Inventors: Amanjot Singh; Leslie Frank Rapchak
Original assignee: Nex Flow Air Products Corp
Current assignee: Nex Flow Air Products Corp
Priority date: 2019-07-22
Filing date: 2020-07-21
Publication date: 2022-09-01
Also published as: EP4004459A4; WO2021012045A1; EP4004459A1; CA3148276A1

Abstract

The present disclosure relates to a vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising: a hot end; a cold end opposed to the hot end; a vortex generator between the hot end and the cold end, the vortex generator configured to receive a working fluid, the vortex generator comprising: a vortex chamber including a bottom wall defining a bore therethrough; and a plurality of channels configured to direct the working fluid into the vortex chamber, wherein one or more of the bottom wall and the plurality of channels are configured to direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber and towards the hot end; and wherein a first working fluid exits the hot end and a second working fluid is turned away from the hot end and flows through the bore to exit the cold end. The present disclosure also relates to use of the vortex tube for panel and spot cooling.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a national phase application of PCT application No. PCT/CA2020/051006, internationally filed on Jul. 21, 2020, which claims priority to U.S. Provisional application No. 62/876,936 filed Jul. 22, 2019 and U.S. Provisional application No. 62/987,070 filed Mar. 9, 2020, which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to a cooling system comprising a vortex tube and methods of using the cooling system.

BACKGROUND

Cold air is typically generated using traditional air conditioning systems. Cold air is used for spot or area cooling as well as for cooling electrical and electronic enclosures. The problem with traditional refrigeration and air conditioning products is the use of chemical refrigerants which in the past have been ozone depleting. Newer materials have a much less effect on the ozone but now raise CO₂concerns. The refrigerants now being developed address the CO₂concerns but they are flammable. In industrial environments this should be a concern especially in applications where electrical and electronic control panel air conditioning is commonplace. For small spot cooling applications vortex tubes have been used and continue to be used due to their compact nature. Another application has been their use for air conditioning of control panels in industry where compressed air is available. The main restriction in their use has been the need to use a gas, usually compressed air for their operation and the high compressed air volume necessary for the cooling produced restricting their use either due to energy cost or limited air supply.
It is known to use vortex tube technology as a refrigeration/air conditioning device for spot cooling and for cooling enclosures such as electrical enclosures and control panels by producing a refrigerated air stream directed into the enclosure as well as for cooling tools in dry machining processes.
The vortex tube designs used in the marketplace have not changed significantly for over 50 years. The vortex tube, also known as the Ranque-Hilsch vortex tube, is a device that separates a compressed gas into hot and cold streams. The device has no moving parts. In operation, a pressurized gas is injected tangentially into a vortex generating chamber and accelerates to a high rate of rotation within the tube. The air vortex created moves through the tube toward a hot end but a sufficient back pressure is developed to force some of the air toward the center of the tube and then back in the opposite direction towards a cold end. This back flow becomes cold as it passes through the vortex tube and it forms a cold airstream.
Known vortex tubes include a single or multi-slotted vortex generating piece called a generator. The generator is inside of a chamber from which the air enters into the generator thru the slots to spin the incoming compressed air, and direct it up the long thin tube. In these designs, for the original cold end chamber, the way the spinning air behaved required a long hot end tube. The ratio of the free volume in the cold end chamber to the volume of the generator is in the range of 1 to 1.5:1 and this has been the consistent ratio in vortex tube designs since.
One attempt at increasing efficiency has been to shorten the thin, but long hot end tube. A brake was developed which is an insert that was put into the hot end tube that would slow the spinning air and thereby shortening the hot end tube. In these known designs, the volume of the hot end tube with the brake was roughly equal to the free volume in the cold end chamber. Virtually all designs since this time have incorporated the concept of the brake in the thin tube, and essentially the same cold end chamber and generator designs.
Until now, not a great deal of attention was paid to energy losses created by the old generator and tube designs. Losses are created by restrictions of parts such as the brake itself and the allowable space for the spinning action with focus on the spinning gas and where it impacts within the vortex tube. Moreover, in known designs, there was no real focus on the effect of the actual volume at the cold end chamber which holds the generator that causes the air to spin.
The limitation in using vortex tubes has always been compressed air energy cost. Therefore, for spot cooling like in tool cooling, if a vortex tube could be more efficient it can extend its use in machining compared to using other gases. For air conditioning of control panels, they are in very dirty environments where high maintenance costs tend to offset much of the energy cost. If a vortex tube can have its efficiency increased even by 10%, it will reduce its use of compressed air energy significantly in existing applications and open up additional applications that were less attractive before, instead of using environmentally negative chemical based air conditioners that have a flammability issue intrinsic to their design.
Therefore, current vortex tube-operated enclosure coolers, which employ known vortex tube designs could benefit from modifications intended to increase in efficiency and allow for additional applications for vortex tubes for both cooling and refrigeration uses.

SUMMARY OF THE INVENTION

It is an embodiment of the present invention to provide a system that addresses efficiency losses to achieve a vastly improved efficiencies of 30% or more as well as the ability to generate lower cold end temperatures with less energy. In one aspect, the present invention provides a system that minimizes the losses attributed to the creation of the spinning action.
The system offers has an efficiency increase of a minimum of 20% to 80% over previous vortex tube designs depending on the various embodiments. In addition to the improved efficiency, the heat sink design and hot end exhaust is configured such that the heat sink never becomes too hot to the touch. The temperature is very minimal. Also, the system is relatively quiet because the system is adaptable for producing little or no exhaust from the hot end.
In one embodiment, there is provided a vortex tube having a cold end volume to the generator volume ratio of between 2 to 5:1.
In one embodiment, there is provided a vortex tube having a sidewall and a plug at the hot air end, the vortex tube configured to exhaust hot air out of the hot end between the sidewall and the plug, each of the sidewall and plug including contoured surfaces sufficient for creating a Coanda effect which mixes the surrounding air with the exhausted hot air and moving the mixed air over the exterior of the hot air end to cool the tube.
In one embodiment, there is provided a vortex tube having a sidewall and a plug at the hot air end, the vortex tube configured to exhaust hot air out of the hot end between the sidewall and the plug, each of the sidewall and plug including contoured surfaces sufficient for creating a Coanda effect which mixes the surrounding air with the exhausted hot air and moving the mixed air over the exterior of the hot air end to cool the tube, wherein the sidewall includes one or more features on the outside surface for increasing the surface area.
In one embodiment, there is provided a vortex tube having a sidewall and a plug at the hot air end, wherein the sidewall defines one or more grooves such that when the plug is inserted into the vortex tube, each one of the grooves forms one exhaust channel between the plug and the sidewall for moving hot air away from the hot air end, wherein the sidewall and plug are arranged so that hot air out can exhausted of the hot end through an opening formed between the sidewall and the plug.
In one embodiment, there is provided a vortex tube having a sidewall and a plug at the hot air end, wherein the sidewall defines one or more grooves such that when the plug is inserted into the vortex tube at the hot air end, each one of the grooves forms one exhaust channel between the plug and the sidewall for moving hot air away from the hot air end and into a chamber formed between the sidewall and the plug, wherein the diameter of the chamber increases moving towards the plug to draw the hot air out via the exhaust channels, and wherein the sidewall and plug are arranged so that hot air can be exhausted out of the chamber through an opening formed between the sidewall and the plug.
In one embodiment, the Coanda cooling system is used to cool the heat sink, the exhaust is limited to 0.5% to 30% of the total air input. This also reduces the noise at that end significantly. The system allows one to have the cold end temperature with minimal hot end exhaust compared to traditional vortex tube which needs to exhaust at least 20% or more at the hot end to achieve the same temperature. The cooling effect is a constant times the air flow at the cold end times the temperature difference from the cold end to a reference hot temperature the cold air is exposed to. Comparing to a traditional system which “wastes” at least 30% air at the hot end (80% cold end) to one where a maximum of 3% is exhausted at the hot end (97% at the cold end), both with the same cold end temperature this represents a minimum efficiency increase of 39%. The tested efficiencies have been increased at least over 20%. With additional changes made at the generator end efficiencies have increased to as high as 80%.
In one embodiment, the plug is a conical plug and has an angle of 30 degrees to 75 degrees, or preferably 45 to 60 degrees.
In one embodiment, there is provided a vortex tube having a plug at the hot air end, the plug comprising an opening configured to draw in atmospheric air towards the cold end to increase the volume of the cold air.
In one embodiment, there is provided a vortex tube including a conical brake at the hot end, the brake secured to the sidewall of the tube at the hot end with its conical tip pointed towards the cold end, the brake includes a plurality of exhaust passages radially spaced outwards from the longitudinal center of the brake and the conical tip is configured to direct any hot air to the sidewalls of the tube and up and through the body of the brake; and a plug secured over the brake at the end opposed to the conical tip and over the exhaust passages, wherein the plug is configured to direct hot air, that has exited the body of the brake via the exhaust passages, through an opening between the plug and the brake and out the hot end of the tube.
In one embodiment, there is provided a vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising: a hot end; a cold end opposed to the hot end; a vortex generator between the hot end and the cold end, the vortex generator configured to receive a working fluid, the vortex generator comprising: a vortex chamber including a bottom wall defining a bore therethrough; and a plurality of channels configured to direct the working fluid into the vortex chamber, wherein one or more of the bottom wall and the plurality of channels are configured to direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber and towards the hot end; and wherein a first working fluid exits the hot end and a second working fluid is turned away from the hot end and flows through the bore to exit the cold end.
In one aspect, the one or more of the bottom wall and the plurality of channels are at an angle of about ±6 degrees from the horizontal. In one aspect, the angle is about 1.93 degrees from the horizontal. In one aspect, the one or more of the bottom wall and the plurality of channels are configured to direct the working fluid in the vortex motion out and towards the wall of the tube so as to reduce mixing between with the second working fluid flowing in an inner area away from the wall of the tube.
In one aspect, the plurality of channels are tangentially disposed about the circumference of the vortex chamber.
In one aspect, the inner diameter of the vortex tube increases in a direction moving away from the vortex generator and towards the one or more of the hot end and the cold end.
In one aspect, the vortex tube further comprises an air inlet chamber configured to receive the working fluid via an air inlet. In one aspect, the volume of the air inlet chamber is about 2 to about 5 times the volume of the vortex generator.
In one aspect, the vortex tube further comprises an end plug coupled to the hot end of the vortex tube, the end plug comprising: a body, the body comprises a lower portion configured to separate the working fluid into the first working fluid and allow the exit of the first working fluid from the vortex tube through an exit aperture formed between the body and the wall of the vortex tube and into the second working fluid and direct the second working fluid away from the hot end and towards the cold end.
In one aspect, the lower portion terminates at a conical tip.
In one aspect, the conical tip includes a conical angle from about 30 degrees to about 75 degrees for generating a second toroidal motion and causing the second working fluid to move away from the hot end towards the cold end. In one aspect, the conical angle is from about 45 degrees to about 60 degrees. In one aspect, the second toroidal motion comprises a laminar flow.
In one aspect, the interior wall at the hot end defines a plurality of circumferentially disposed slots for channeling the first working fluid between the lower portion and the wall of the vortex tube. In one aspect, the plurality of circumferentially disposed slots are semi-circular.
In one aspect, the thickness of the interior wall at the hot end along the length of plurality of circumferentially disposed slots is sufficiently thin to promote dissipation of thermal energy. In one aspect, the width and/or length of the plurality of circumferentially disposed slots is dimensioned to maximize a rate of flow of the first working fluid while maintaining a sufficient transfer of thermal energy into the wall such that the first working fluid exiting the vortex tube has a reduced thermal energy. In one aspect, the first working fluid exiting the plurality of circumferentially disposed slots enter into a chamber having outwardly flaring walls for drawing the first working fluid out of the vortex tube.
In one aspect, the body further comprises cap with an outer perimeter having a contoured surface configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube and to cling to outer wall of the vortex tube and thereby reducing the temperature of the hot end of the vortex tube. In one aspect, the contoured surface forms an angle of about 45 degrees from the horizontal. In one aspect, the end plug is axially moveable in relation to the vortex tube to adjust the diameter of the exit aperture formed between the end plug and the vortex tube. In one aspect, the diameter of the exit aperture formed between the end plug and the vortex tube is adjustable to limit the exhaust from the hot end to about 0.5% to about 30% of the total amount of working fluid directed into the vortex generator. In one aspect, the diameter of the exit aperture formed between the end plug and the vortex tube is adjustable to limit the exhaust from the hot end to about 0.5% to about 30% of the total amount of working fluid directed into the vortex generator.
In one aspect, the vortex tube further comprises a heat sink disposed at the hot end, the heat sink comprising a plurality of spaced apart fins disposed along the wall at the hot end and configured to dissipate thermal energy generated within the interior of the vortex tube away from the wall. In one aspect, the plurality of spaced-apart fins extend outwardly about the longitudinal center of the vortex tube. In one aspect, each of one the plurality of spaced-apart fins comprises a contoured surface configured to flow the combined air away from the hot end and towards the cold end. In one aspect, the contoured surface is a rounded surface. In one aspect, the contoured surface of an end fin adjacent to the end of the hot end defines a second contoured surface that is co-linear with the contoured surface of the cap and is configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube.
In one aspect, the end plug defines an air channel configured to move the surrounding air into the interior of the vortex tube and in the direction of the cold end to increase the volume of the second working fluid exiting the cold end. In one aspect, the air channel is about 2% to about 20% of the diameter of the vortex tube at the hot end.
In one aspect, the vortex tube further comprises a liquid cooling vessel disposed between the end plug and the wall of the vortex tube and sealingly secured to the vortex tube to enclose the hot end, the liquid cooling vessel including a liquid inlet and a liquid outlet for delivery and removal, respectively, of a cooling liquid used to cool the hot end.
In one aspect, the cap is removably coupled to the lower portion, and the lower portion defines a plurality of circumferentially disposed exhaust passages for channeling the first working fluid through the lower portion and then out of the vortex tube. In one aspect, the cap comprises an elongate connecting member and the lower portion defines a slot configured to receive the elongate connecting member. In one aspect, the cap and the lower portion are threadably coupled.
In one aspect, the vortex tube further comprises a delivery tube couplable to the cold end for spot cooling. In one aspect, the delivery tube is a flexible delivery tube.
In one embodiment, there is provided an assembly for a panel cooler, the assembly comprising a vortex tube of the present disclosure; and a housing dimensioned to surround the hot end of the vortex tube, the housing including one or more seals configured to allow movement of gas out of the housing and to prevent movement of water into the housing; wherein the cool end of the vortex tube is couplable to the panel cooler and directs the second working fluid into the interior of the panel cooler. In one aspect, the vortex tube further comprises a back pressure exit port at the cold end configured to route back pressure out of the panel cooler and out to the atmosphere.
In one embodiment, there is provided a vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising: a hot end; a cold end opposed to the hot end; a vortex generator between the hot end and the cold end, the vortex generator configured to receive a working fluid, the vortex generator including a bottom wall defining a bore therethrough and configured to direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber and towards the hot end; and an end plug coupled to the hot end of the vortex tube, the end plug comprising: a body, the body comprises a lower portion configured to separate the working fluid into the first working fluid and allow the exit of the first working fluid from the vortex tube through an exit aperture formed between the body and the wall of the vortex tube and into the second working fluid and direct the second working fluid away from the hot end and flows through the bore to exit the cold end.
In one embodiment, there is provided a vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising: a hot end; a cold end opposed to the hot end; a vortex generator between the hot end and the cold end comprising a vortex chamber comprising a bottom wall defining a bore therethrough, the vortex chamber configured to receive a working fluid and direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber and towards the hot end; and an end plug coupled to the hot end of the vortex tube, the end plug comprising: a body, the body comprises: a lower portion configured to separate the working fluid into a first working fluid and into a second working fluid and directing the second working fluid away from the hot end and through the bore to exit the cold end; a plurality of circumferentially disposed exhaust passages for channeling the first working fluid separated by the lower portion through the body; and one or more exhaust ports for exhausting the first working fluid out of the body and away from the vortex tube.
In one aspect, the body further comprises cap with an outer perimeter having a contoured surface configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube and to cling to outer wall of the vortex tube and thereby reducing the temperature of the hot end of the vortex tube. In one aspect, the contoured surface comprise a convex surface. In one aspect, the contoured surface further comprises an angle of about 45 degrees from the horizontal.
In one aspect, the plurality of circumferentially disposed exhaust passages comprise an inlet arranged so that the first working fluid enters into the body at an angle about perpendicular to the longitudinal axis of the tube.
In one aspect, the end plug is axially moveable in relation to the vortex tube to adjust the diameter of the one or more exhaust ports. In one aspect, the diameter of the one or more exhaust ports is adjustable to limit the exhaust from the hot end to about 0.5% to about 30% of the total amount of working fluid directed into the vortex generator. In one aspect, the diameter of the one or more exhaust ports is adjustable to limit the exhaust from the hot end to about 0.5% to about 30% of the total amount of working fluid directed into the into the vortex generator.
In one aspect, the vortex tube further comprises an air inlet chamber substantially surrounding the vortex chamber and in fluid communication with the vortex chamber, wherein the vortex chamber comprises concave walls so as to increase the volume of the air inlet chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional view of a vortex tube in accordance with an embodiment of the invention;

FIG. 2a is a perspective view of the vortex tube in FIG. 1;

FIG. 2b is a top view of the of the vortex tube as shown in FIG. 1;

FIG. 3a is a side view of a vortex generator in accordance with an embodiment of the invention;

FIG. 3b is a cross section of the vortex generator alone the line 3 b-3 b in FIG. 3 a;

FIG. 3c is top view of the vortex chamber in accordance with an embodiment of the invention;

FIG. 4 is a side view of an end plug in accordance with an embodiment of the invention;

FIG. 5a shows a side view of the heat sink in accordance with an embodiment of the invention;

FIG. 5b shows a cross sectional view of the heat sink along line 5 b-5 b in FIG. 5 a;

FIG. 5c shows a top view of the heat sink in FIG. 5 a;

FIG. 6a shows features of the end plug and heat sink of inset A in FIG. 1 in accordance with an embodiment of the invention;

FIG. 6b shows features of the end plug and heat sink in accordance with an embodiment of the invention;

FIG. 7 is a cross sectional view of a vortex tube showing a plug with an opening configured for air entry in accordance with an embodiment of the invention in accordance with an embodiment of the invention;

FIG. 8 is an enlarged cross sectional view of the hot end of a vortex tube showing a plug with an opening configured for air entry in accordance with an embodiment of the invention;

FIG. 9a is a cross sectional view of a vortex tube used to cool an enclosure in accordance with an embodiment of the invention;

FIG. 9b shows features of inset C in FIG. 9a showing portions of a heat sink in accordance with an embodiment of the invention;

FIG. 10 is a cross sectional view of a vortex tube for use in cooling an enclosure in accordance with an embodiment of the invention;

FIG. 11 is a cross sectional view of a vortex tube configured for liquid cooling in accordance with an embodiment of the invention;

FIG. 12a is a cross sectional view of an adjustable exhaust plug and brake in accordance with an embodiment of the invention;

FIG. 12b shows features of inset C in FIG. 12 a;

FIG. 12c is a side view of the brake of FIG. 12 a;

FIG. 12d is a top view of the brake of FIG. 12 c;

FIG. 12e is a cross section along the line 12 e-12 e of FIG. 12 c;

FIG. 12f is a side view of the plug of FIG. 12 a;

FIG. 13a is a cross sectional view of an adjustable exhaust plug and brake for use in cooling an enclosure in accordance with an embodiment of the invention;

FIG. 13b shows features of inset C in FIG. 13 a;

FIG. 13c is a side view of the brake of FIG. 13 a;

FIG. 13d is a top view of the brake of FIG. 13 c;

FIG. 13e is a cross section along the line 13 e-13 e of FIG. 13 c;

FIG. 13f is a side view of the plug of FIG. 13 a;

FIGS. 14a and 14b show a cross sectional view and a perspective view, respectively, of a vortex tube having a flexible portion attached to the cold end, in accordance with another embodiment of the invention;

FIGS. 14c, and 14d show a cross sectional view and a perspective view, respectively, of the vortex tube of FIGS. 14a and 14b where the flexible portion is bent;

FIG. 15a is a side view of a vortex tube in accordance with an embodiment of the invention;

FIG. 15b is a cross sectional view of along the line 15 b-15 b of FIG. 15 a;

FIG. 15c is a perspective view of a plug in accordance with an embodiment of the invention shown in isolation;

FIG. 15d is a side partially transparent view of the plug;

FIG. 16a is a side view of the vortex generator of the vortex tube of FIG. 15a in accordance with an embodiment of the invention; and

FIG. 16b is a cross section view along the line 16 b-16 b of FIG. 16 a.

DETAILED DESCRIPTION

Reference will be made below in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals used throughout the drawings refer to the same or like parts.
According to an embodiment, with reference to FIGS. 1 to 6 b, we disclose a vortex tube 10 which is generally an elongated tube having a hot end 12 and an opposed cold end 14. Disposed between the hot end 12 and the cold end 14 is a vortex generator 20 comprising a vortex chamber 22 and an air inlet chamber 24 having an inlet 26 having a cold air volume. The vortex chamber 22 and the air inlet chamber 24 are fluidly connected by a plurality of channels 28 tangentially disposed about the circumference of the vortex chamber 22 and configured to flow a working fluid (such as a compressed gas) from the air inlet chamber 24 into the vortex chamber 22. The vortex chamber 22 includes a bottom wall 30 defining an exit aperture 32. The vortex generator 20 is configured to direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber 22 and towards the hot end 12 along a length (L) the vortex tube 10 having a diameter (D) at its thickest point. As a consequence of the toroidal movement of the working fluid, the length of vortex tube 10 (also known as the hot end tube 34) between the vortex generator 20 and the hot end 12 has an increased temperature. The hot end tube 34 can have an inner diameter which increases from its narrowest width (d) near the vortex generator 20 and to its widest with (D) near the hot end 12.
As will be discussed in further detail below, the working fluid imparted with a toroidal motion flows through the hot tube 34 and near the hot end 12 is then caused to separate into a first working fluid stream and into a second working fluid stream. The first working fluid then exits the hot end 12 and the second working fluid which has as lower relative temperature is turned away from the hot end 12 and then flows against the flow of the working fluid in an inner lower pressure area and then through the exit aperture 32 of the vortex chamber 22 and flows into a cold end tube 36 before exiting the cold end 14. Cold end tube 36 can have an inner diameter which increases from its narrowest width (d′) near the vortex generator 20 and to its widest with (D′) near the cold end 14.
In one aspect, the flaring of the hot end tube 34 allows for control in the spinning action as the first working fluid moves within the hot end tube 34 towards the hot end 12. Similarly, the flaring of the cold end tube 36 increases the velocity of the second working fluid. The tapering of the hot end tube 34 and/or of the cold end tube 36 can be accomplished using a tapered sleeve or the tapering can be built into the vortex tube 10. The reduction of back pressure and pressure loss allows for a dramatic increase in spinning velocity and momentum. The shape of the generator 20 is such that it allows more volume to be in the cold end chamber 24 which minimizes the pressure loss thereby creating a faster spin and this drives the temperature lower. This higher spinning also removes any condensed moisture to the outer spinning area, and up and out the vortex tube 10. The sleeve angle is calculated such that the centrifugal force of the air stream moving up to the hot end 12 increases (spinning gets faster) and/or the upward velocity increases up the hot tube 34 and stabilizes the temperature at both the cold and hot end 12. In traditional generator designs the spinning is unstable causing temperature fluctuations. The new design eliminates this instability because it reduces turbulence and pressure drops.
According to an embodiment, with reference to FIGS. 1 to 3 c, the cold end volume of the air inlet chamber 24 is increased to a minimum of two times the volume of the generator 20 (as shown using shading) compared to the old vortex tube designs. As a consequence, it has been revealed that the cooling effect would be increased drastically and that the length (L) of the hot end tube 34 could be reduced by about 20% to 40% and thus eliminating the requirement for a brake. In an aspect, the volume of the hot end tube 34 is approximately 60% less than the known designs and consequently the length (L) can be much shorter. Without being limited to any particular theory, it is believed that such modification was able to change the spinning action inside the vortex tube 10 with the larger volume of the cold end chamber 24.
In some aspects, the length of the hot end tube 34 may be dependent on both the volume of the cold end chamber 24 and the capacity of air flow of the generator 20 (FIGS. 3a to 3c ) (which is discussed below) and will also vary with the inside diameter of the tube 10. The inside diameter of the tube 10 can also vary with the capacity of the air flow. In aspects, as the air flow capacity increases, which is dependent on the size of the generator 20 (FIGS. 3a to 3c ), cold end volume of the chamber 24 and air inlet 26, the inside diameter (D) can also be increased to accommodate a wider spinning action.
This present system is much more compact and eliminates any losses by the brake as will be discussed below (which, in one or more embodiments, is no longer necessary). This system consumes air or gas with minimum pressure losses in the cold end chamber 24 and generates a higher-pressure toroidal air flow with minimal losses as will be discussed below.
In one embodiment, the present disclosure relates to a vortex tube 10 has an increased volume of the cold end chamber 24 to reduce losses. Having the cold end volume ratio a minimum of two to a maximum of five times the volume of the generator chamber 22 provides for a more compact and efficient vortex tube 10. In some embodiments, if a higher pressure is supplied to the air inlet 26, the cold chamber 24 volume can be increased up to 5 times (FIGS. 3a to 3c ). The present disclosure is in contrast to known vortex tube designs which are less efficient because gas flow is controlled primarily by the generator size. In known designs, with only a minimal cold end volume in the chamber 24, the pressure is not able to build up due to air passage restrictions in the cold end chamber.
According to an embodiment and with reference to FIGS. 3a to 3c , there is provided an improved vortex generator 20. In one aspect, the generator 20 is configured such that a high pressure spinning toroidal air flow is produced through channels 28 at a specific toroidal diameter D_gwithin the vortex chamber 22 in the generator 20 and the actual air consumption is dependent on the depth of the channels 28 and the range of suitable dimensions is dependent on the vortex tube size. The toroidal diameter D_gand the volume of vortex chamber 22 is dependent on the volume of the incoming air flow through the generator channels 28 as well as the pressure. In aspects, the volume of the hot end tube 34 is in a range of about 10 to about 15 times the sum of the volume of the generator channels 28 and this range depends on the pressure of gas entering the vortex generator 20. The diameter of the hot end tube to the inside diameter of the generator D_gwhere the air is spinning should be in the range of about 1.5:1 to about 2:1.
Additionally, the vortex generator 20 includes an angle formed from the bottom wall of chamber 22 of the generator 20. This angle may be a tapered angle that uses the Coanda effect to draw the air away from an area near the bottom wall 30 and towards the hot end 12. The tapered angle can be anywhere from about + or −6 degrees from a horizontal plane perpendicular to a longitudinal central axis of the tube 10 or preferably, from about 1.9 degrees, or more preferably about 1.93 degrees, from the horizontal depending upon the physical size of the vortex tube 10 and also depending on outside instances where the cold end 14 may encounter back pressures (for high back pressures the angle may increase and for low back pressures it might decrease).
Without being limited to any particular theory, the tapered angle uses assists in directing the air upwards preventing the cold air produced from mixing with the other toroidal spinning air which is moving away from the cold end 14. This creates a barrier between the hot and cold air. The cold air therefore is maximized. This is in contrast to known designs where some of the cold air produced is drawn up toward the hot end 12 along with the hot air. In one aspect, the tapered angle assists in directing the outside spinning air upwards preventing the cold air from the inside spinning column mixing with the outside spinning column. As well, without being limited to any particular theory, the elimination of this mixing keeps the inside column colder.
In one embodiment, the disclosed generator 20 and tapering effect of one or more of the hot end tube 34 and the cold end tube 36 significantly improves the cooling effect on the second working fluid. In some aspects, the result is a 50-60% improvement in cooling.
In some aspects, a negative angle can be used if the inlet pressure is very high (in the range of 1000 PSIG or higher) as the negative angle controls the temperature buildup at the hot end 12 due to higher energy input caused by the higher pressure.
In known vortex tubes a brake is included to slow the spin of the gas in the hot end tube 34 so that the tube length (L) can be reduced or can be controlled. However, it has been found that this brake inside the hot end tube 34 acts as a restriction to the air flow and causes some energy loss. It also causes heating in and around the brake. In the past, a significant amount of research was done to improve the brake.
According to an embodiment and with reference to FIGS. 1 to 4, the vortex tube 10 further comprises an end plug 40 and a hot end air release system that allows the hot end waste air to blow back down over the hot end 12 of the vortex tube 10 utilizing the Coanda effect.
According to the embodiment shown in FIGS. 1 and 3, the brake is eliminated and instead the end plug 40 is configured so that it is able to control the exit of the hot end air. The end plug 40 is secured at the end of the hot end tube 34. The end plug 40 at the hot end 12 controls the velocity and the cooling with minimal energy loss and reduces restrictions in the generation of the cold toroidal (spinning) gas. Less heat is generated. The end plug 40 comprises a body 42, a cap 44 defining an outer perimeter 46, and a lower portion 48.
The lower portion 48 includes a particular angle range to minimize energy losses. In one embodiment, the lower portion 48 terminates at a conical tip having a conical angle that varies from about 30 degrees to about 75 degrees. In aspects, the conical angle can vary from 45 degrees to 60 degrees.
The disclosed conical angle range enables effective and efficient control of the cold end velocity and cooling. Without being limited to any particular theory, the disclosed angles help form the second toroidal with laminar flow and increase the velocity of the cold air (i.e. second toroidal) with minimal friction losses.
The cap 44 contributes to the end plug hot end air release system that allows the hot end waste air to blow back down over the hot end 12 of the vortex tube 10 utilizing the Coanda effect. As shown in FIGS. 6a and 6b , the first working fluid exits the vortex tube 10 via an exit aperture 59 formed between the body 42 of the end plug 40 and the wall of the hot end 12 of the vortex tube 10. As shown in FIGS. 6a and 6b , the contoured surface of the outer perimeter 46 is configured to draw air surrounding the vortex tube 10 for mixing with the first working fluid exiting from the vortex tube 10 (via the exit aperture 59) and to cling to outer wall of the vortex tube 10 and thereby reducing the temperature of the hot end 12 of the vortex tube 10. With this effect, air is entrained along with the hot air and directed downward along the hot end tube 34. This causes the hot tube 34 to be cooled, and as the heat was removed by this cooling, the cold end temperature was also reduced. In aspects, the contoured surface of the outer perimeter 46 is about 45 degrees from the horizontal so as to be able to flow air back over the hot end tube 34.
According to an aspect, this change achieves 0° C. to −10° C. cold end temperature by exhausting only 5 to 8% of the compressed air initially compared to 20% to 30% needed in current designs. As well, since the air flowing out of the hot end 12 follows a Coanda profile, this greatly reduces the noise level as the hot air mixes with entrained ambient air.
According to an embodiment and with reference to FIGS. 7 and 8, a plug 140 is provided that can be threadably secured to the hot end 12, the plug 140 can further comprise an opening 142 that passes through the plug. In this embodiment, the hot end cooling assembly actually draws in some atmospheric air which goes to the cold end 14, increasing the volume of the cold air as well as lowering the temperature further. The range of the opening diameter should be 2% to 20% of the hot tube diameter (D). This design is for applications where lower sub-zero temperatures are required for cooling. In aspects, the air drawn into this opening would be assisted by a Coanda effect arising from the plug whereby the Coanda effect provided by a tapered angle 144 at conical tip 48 inside the vortex tube. In some aspects, this tapered angle is 45 degrees which causes the drawing in of the air around the angles, which, as the air directs downward, creates a vacuum that effects all the way up inside the hole in the plug drawing in the fresh air from the outside because of the vacuum. As shown in FIG. 8, plug 140 can also be used in combination with a heat sink 50 (as described below) and in panel cooler applications (not shown), where the cold air outlet, however, could be more susceptible to backpressure. The extra back pressure caused by air blown into the enclosure can be dealt with by using relief valves or other systems for panel coolers to relieve pressure from inside the enclosure (not shown).
In aspects, the present disclosure provides for ways to dissipate the heat built up inside the hot end tube 34 and/or minimize noise, and/or improve cooling performance and increase energy efficiency as shown in FIGS. 1 to 5 c.
According to an embodiment and with reference to FIGS. 1 to 6 b, the system includes a heat sink 50 that comprises features to help draw the hot air out of the tube 10. While traditional heat sinks have been tried before on vortex tubes, it was found these traditional heat sinks were not able to remove the heat fast enough.
In one aspect, the heat sink 50 may have a plurality of spaced-apart fins 52 disposed at the hot end 12 to dissipate thermal energy generated with the interior of the vortex tube 10 away from the wall 57 of the hot tube 34. The plurality of spaced-apart fins 52 maximize surface area and a gap 54 between the fins or serrations 52 is suitably dimensioned to let the heat escape when the amplified air from the hot end exhaust blows over the heat sink 50. Additional considerations may include strength and integrity of the material used. Fins 52 may be made, for example, from materials such as brass or stainless steel. An end fin 55 is provided adjacent the end of the hot tube 34 which has a second contoured surface 56 that is collinear with the contoured surface 46 of the cap 44.
In aspects, as shown in FIGS. 6a and 6a there is provided with rounded edges or slightly beveled and round edges, respectively, on the fins that are configured to draw out the hot air from around the fins as the amplified air from the hot end 12 of the vortex tube 10 is drawn into the fin area to cool this area. When the Coanda effect is enhanced by the angles on the fin edges, this improves heat removal.
In one aspect, there is provided a direct contact between the heat sink 50 and wall 57, such that heat already begins to transfer from the hot escaping air, into the heat sink 50, cooling the hot escaping air exiting the exit aperture 59. Utilizing the plug 40 and hot air release system at the hot end 12 with the Coanda effect to blow the hot air exhaust along with entrained air over the heat sink 50 of adequate size was able to keep up with the heat generated and to remove the heat.
In an embodiment, and with reference to FIGS. 5a to 5c , the sidewall 57 of the hot end 12 defines one or more circumferentially spaced exhaust channels 60. When the plug 40 is inserted into the hot end 12, the exhaust channels 60 provide a passageway for hot air to move between the plug 40 and the wall 57 and to exit the passageway 60 through respective exhaust holes. The channels 60 and exhaust holes of the heat sink 50 are configured to maximize the heat buildup so that heat can be transferred to the vortex tube wall 57.
In one aspect, the channels 60 and thus, the exhaust holes, are semicircular or substantially semicircular shape in order to generate maximum turbulence which will create and localize the heat inside the channels 60 and exhaust holes to maximize heat buildup. The number of channels 60, and exhaust holes and/or the dimensions of the channels 60 and exhaust holes are configured to allow for sufficient flow of hot gas under a controlled backpressure and maximize heat buildup. The length of the channels are sufficiently long enough to be able to adjust the amount of gas released to the outside from the holes, but short enough to concentrate the heat buildup. In some aspects, sidewall 57 is thin in the area of the exhaust channels 60 such that heat from the hot air within the channels 60 can be conducted into and through the sidewall 57. In aspects, the tube 10 is made from a material that has sufficient strength to maintain the integrity of the sidewall 57 at least around the area of the channels 60 and exhaust unit. The result is that the hot air that exits is colder (because the heat is concentrated in the holes), and then cooled even more when entraining the outside air, providing an optimum cooling medium over the outside of the heat sink 50.
The channels 60 and exhaust holes are dimensioned to be able handle the volume of the exiting air but small enough to build up the heat. When this design is used, it also keeps the temperature cool enough to the touch. In known vortex tube designs, the hot end 12 gets hot and cannot be touched with bare hands. In contrast, with the disclosed heat sink 50 and cooling system, the hot end 12 does not get hot to the touch which enhances safety. In some embodiments, it is possible to achieve a continuous −35° C. temperature at the cold end 14, without heating up the hot end 12 beyond a “warm level” because of the heatsink and cooling system with the Coanda effect exhausting only 5%-8% air out the hot end 12. This compares to exhausting over 50% of the air out to achieve the same cold end temperature with traditional designs. Again this translates into a tremendous energy saving expanding possible uses for the vortex tube 10 in small refrigeration applications where sub-zero temperatures are required.
As shown in FIG. 5b , the hot air exits through the exhaust holes to enter a chamber 70 defined by the sidewalls 57 of the tube 10 and the plug, where the end wall forms an angle formed by the wall of the tube 10, the angle and the formed chamber 70 which increases in diameter moving towards the hot end 12 wherein the diameter of the chamber 70 increases moving in the direction towards the hot end 12 and the plug to help draw the hot air out of the tube 10. In aspects, this feature of the end wall of the tube 10 helps overcome losses at the exit allowing the hot air to escape.
The heat sink 50 is dimensioned and configured to remove heat with a starting temperatures of 60 C to 450 C as quickly as possible without retaining that heat within the heat sink 50 and fins 52. With this heat sink design, only 0.5% to 10% of the compressed air is exhausted at the hot end 12 compared to 20% to 30% in original vortex tube designs to achieve a cold end temperature between 0° C. to −5° C. This translates to a significant energy reduction in cooling in the range of 50%. Again, the sufficiently sized heat sink 50, with the angles on the layered fins 52, and the Coanda effect move the hot air exhausted out of the hot end 12 and down over the heat sink 50 with the entrained air removes heat effectively away from the vortex tube 10.
The diameter (D) also affects the hot tube length (L) and the length of the hot end tube 34 can be set to a length where no heat is generated at the air exit by use of the heat sink(s) according to the present disclosure. The above change produces a high velocity air flow at the cold end 14 which further increases the BTU per hour and lower temperatures were achieved as compared to the original design. In known vortex tubes, for given diameter (D), if length (L) is increased, this will result in a hotter hot end 12 which translates to a colder cold end 14. Therefore, according to the present disclosure, the vortex tube 10 can achieve much shorter lengths (L) for any given diameter (D). However, if circumstances require additional length (L) to generate more heat, then the provision of the heat sink 50 will reduce the additional heat.
Without being limited to any particular theory, it is believed that when the first toroidal spinning air (outside spinning tube) hits the cone shaped hot end plug 40 which is at specific calculated angle, the second toroidal is generated back inside the first one (it curves back down inside itself). When the 2nd toroidal starts to move downwards to the cold end 14 the 1st toroidal transfers its spinning energy to the 2nd toroidal making it spin faster and when it reaches close to the generator 20 the spins are at the maximum revolutions and the maximum cooling is achieved. The generator 20 according to the present disclosure avoids any anticipated losses in the spinning air. In aspects, the angle is ±about 6.00 degrees. In other aspects, the angle is about 1.93 degrees from the horizontal. In further aspects, the flow of gas is directed towards the hot end 12 by the generator 20.
With the aforementioned features, it was possible to achieve very cold temperatures to the −35 degrees C. range. Additionally, by altering the hot end assembly that uses the Coanda effect to direct the hot end exhaust and entrain outside air down over the heat sink 50, and the extending the heat sink 50 down further along the hot tube 34 it was possible to generate temperatures as low as −50 degrees C. at the cold end 14 with only 5 to 8% air exhausted at the hot end 12. In aspects, the increased volume in the cold end increases the spinning speed from the generator 20 because of less pressure loss. The increased spinning speed increases the heat generated at the hot end 12 which is concentrated in the exhaust holes as described earlier. As the spinning air on the inside of the toroid returns toward the cold end 14, it returns with less heat energy as it will have been removed by the hot end design as described earlier. In summary, the very low sub-zero temperatures are achieved is because of the heat removal at the hot end 12 and from the higher spinning speed generated by the generator 20.
One of the most common applications for vortex tubes is the cooling of electrical and electronic enclosures. When used with these units the cold end temperature is set to around −5 C to 0 C to avoid moisture problems inside the control panel. According to an embodiment, and with reference to FIGS. 9a, 9b and 10, the present disclosure provides for a vortex tube 10 that is easily adapted for panel cooling by adding a connection at the cold end 14 with a built in exhaust to remove the hot air displaced by the added cold air from the vortex tube 10.
For example, an existing patent application WO 2010/045707 to Bakos (which is incorporated by reference in its entirety) describes a connection used at the cold end 14 with a seal to prevent any sprayed water from entering the control panel through the holes that exhaust the displaced air. The difference between the device of the present disclosure and known devices is only that there is provided additional holes for exhaust (or larger holes) as more air will go into the control panel, while previously this air would have been wasted at the hot end 12. The presently disclosed system cools faster and will cool with 80% more BTU/hr than known designs. In some aspects, because less air is exhausted at the hot end 12, the system will also be quieter. As the hot end 12 does not get hot (just warm), there is no requirement for a warning or a protective sleeve as in traditional designs.
In some embodiments as shown in FIGS. 9a and 10, the system further includes a cover 80 to prevent sprayed water getting in through the hot end 12. As shown in FIG. 10, the cover is provided with baffles with holes, offset from each other, to let the air out, but avoid sprayed water from getting up to the vortex tube hot end 12. In some aspects, the cover 80 may include a rubber rings. The cover 80 is configured so that it is able to pass the spray test by Underwriter Laboratories (UL) for NEMA 4 (National Electrical Manufacturer Association) level. The spray test is where water is blasted for 12 seconds from a fire hose at the panel cooler and will result in a pass if no water gets inside the panel. For NEMA 12 and NEMA 3R there is no need for seals as it is basically a water mist test only.
According to an embodiment, and with reference to FIG. 11, the present disclosure provides a device that is suitable for use with liquid cooling and/or air cooling. In one embodiment, there is provided a system comprising a vortex tube 10 and a liquid cooling vessel 90 having a liquid inlet 92 and a liquid outlet 94, the vessel 90 configured to carry liquid over the fins 52 to direct heat away from the fins 52. The vessel having a portion 94 disposed between the plug and the wall of the hot end 12 of the tube 10. The system being configured to allow some hot air (e.g. about 1%) or in some embodiments, no hot air, to leave the hot end 12 between the vessel and the plug, where the amount of hot air can be controlled by the adjustment of the distance 96 (i.e. gap distance) between the plug 40 and the vessel 90. According to this embodiment, the vortex tube 10 is able to produce temperatures at the cold end in the range of 0 C to −5 C when the hot end 12 was fully closed (no hot end exhaust).
According to an embodiment, the present disclosure provides a device that is suitable for use with air cooling through the use of fans (not shown) that can be directed towards the fins of the heat sink 50 to assist in the dissipation of heat.
According to an embodiment, the present system provides a compressed air energy savings of around 30% or possibly more over old vortex tube designs. There is less hot end exhaust noise. Since the hot end 12 does not get too hot to the touch, there is an improved safety and also the possibility of use in applications which require explosion proof environment. The liquid cool embodiments also allows for additional refrigeration applications, without any CO₂impact and no ozone depleting chemicals.
For control panel cooling application, the devices and systems according to the present invention increases the range of use especially in very dirty environments where these units are often used. Traditional air conditioners are getting more costly as they move to more expensive refrigerants that do less harm to the environment. However these new refrigerants are (almost all) flammable which creates new issues in some environments while the new design has no issues at all in this area.
The devices and systems of the present disclosure also may be used to create low temperatures as low as minus 40 C which has use as gas analysis vortex tubes. To achieve such low temperatures, the presently disclosed system allows for exhaust up to as much as 80% of the hot end air.
According to an embodiment, with reference to FIGS. 12 and 13, the present disclosure provides for systems that include a cooling assembly with a brake 240 at the hot end 12.
With reference to FIGS. 12a to 12f , system 200 and brake 240 includes a conical tip 248. The brake 240 can be secured to the sidewall of the tube 10 at the hot end 12 with its conical tip 248 pointed towards the cold end. Brake 240 includes a plurality of exhaust passages 250 radially spaced outwards from the longitudinal center of the brake 240 and the conical tip is configured to direct any hot air to the sidewalls of the tube 10 and up and through the body of the brake 240.
A plug 244 is secured over the brake 240 at the end opposed to the conical tip and over the exhaust passages 250. The plug is configured to direct hot air, that has exited the body of the brake 240 via the exhaust passages 250, through a controlled opening 260 between the plug and the brake 240 and out the hot end 12 of the tube 10. The hot air that has exited this controlled opening 260 is subjected to a Coanda effect created, for example, by the combination of the contours of the outer perimeter 262 of the plug 244 and the sidewall 264 of the tube 10 at the hot end 12. The sweeping coanda angle at the outer perimeter 262 and the sidewall 264 permits surrounding air to carry hot air away from the hot end 12 of the tube 10 which cools this end of the tube 10. In some aspects, the sweeping coanda angle is about 45 degrees from the horizontal.
In some aspects, the plug 244 and the brake 240 comprise mutually engaging structures to couple the plug to the brake 240, where for example as shown, the plug 244 includes a male member adapted to be received by a female member defined by the body of the brake 240. In some aspects, the plug 244 and brake 240 include mutually cooperating threads so that the plug 244 can be screwed into the body of the brake 240.
In some aspects, the angle of the conical tip 248 is from about 30 degrees to about 75 degrees, or from about 45 to 60 degrees. In some aspects, the controlled opening is adjustable from 0.002 to 0.100 inches. In some aspects, the formed coanda angle is about 45 degrees.
FIGS. 13a to 13f shows system 300 that is similar to that shown in FIG. 12, except this system is configured to be used to cool an enclosure 400. This system includes a cover 380 that surrounds or substantially surrounds the hot end 12 and a seal 381 that serves as a barrier for water entry. The system also includes an attachment adapter 382 for securing the vortex tube 10 to the enclosure, this adapter 382 including one or more ports 384 for relieving any excess pressures from within the enclosure 400.
According to an embodiment, and with reference to FIGS. 14a to 14d , the present disclosure provides a tube 10 that is configured to utilize the hot air exhausted out of the hot end 12 and over the heat sink 50 via the Coanda effect to eliminate or reduce the formation of condensate that would otherwise form on the outside of the tube 10.
Air from the hot end exhaust exits the inside of the vortex tube 10 and is used to cool the heat sink 50. This exiting air not only flows along the heat sink 50 to remove the built up heat on the heat sink 50 but can advance further along the vortex tube body. The exiting air, which remains warm, is essentially laminar flow and can, in some embodiments, continue along the vortex tube 10 approximately an additional 20 inches past the cold end exhaust.
A delivery tube 410 can be attached to the cold end 14 of the vortex tube 10. The exhausted air 412, which was further warmed when removing the heat from the heat sink 50, will flow along the outside of the attached tube 10. The flow rate and heat is such that it has negligible effect on the cold air flowing inside the tube 10 while its mild movement and warm temperature prevents condensation that could form on the outside of the tube 10 because of the cold air inside the tube 10. In this way, the cold end exhaust, while being delivered at a temperature at least as low as and even lower than minus 40 C, will not have condensation on the delivery tube. In some aspects the attached delivery tube can be a flexible tube such as for example a loc-Line™ tube.
According to another embodiment, we disclose a vortex tube 10 that eliminates or reduces the formation of condensate or ice on the interior of the tube 10 seen in known vortex tube designs. Because significant cold temperatures are generated inside known the vortex tubes, it is recommended to use filtered air to remove any loose moisture in the compressed airline. However, in many applications the dew point (the point at which dissolved moisture can condense from a compressed airline) is passed and water droplets can and do condense out inside the vortex tube 10. This can cause fluctuations in cold end temperature produced when using vortex tubes at sub zero temperatures because as moisture condenses, it forms ice. While these ice droplets quickly melt and the flow starts up again, there is a brief interference with the flow. The vortex tube 10 of the present disclosure eliminates much of the turbulence that causes such flow interference.
The vortex tube 10 of the present disclosure is configured so that the generated spinning is such that any moisture that condenses out when the temperature falls below the dew point, is thrown to the outside spinning area of the compressed air by centrifugal force. Since the outside spinning air is warmer, any condensed droplets do not freeze.
In addition, the air pressure of this spinning air is less than line pressure and thus has a lower dew point such that any moisture dissolves back into this spinning warm air as warm air can absorb more moisture. Thus any moisture is dissolved in the warm air and then carried up to the hot end 12 of the vortex tube 10, which has a temperature of around 45° C., and then expelled with the hot air exiting the vortex tube 10, fully dissolved into the air which then is used to cool the heat sink 50. Any moisture in fact can only aid in the cooling of the heat sink 50.
As tested, with a plant compressed air supply with a dew point of close to, but above 0 degrees C., sub-zero temperatures to −40° C. and lower have been produced without any condensation in the cold air delivered despite the temperature falling well below the dew point.
When used in applications such as control panel enclosure cooling, high cooling efficiencies can be achieved by using much colder temperatures in addition to the fact that a higher percentage of input compressed air flows as well to the cold end outlet.
For the above reasons, traditional vortex tube 10 coolers have exit cold air temperatures close to zero degrees C. because of dew point concerns. In contrast, the vortex tube 10 of the present disclosure eliminates this dew point caused condensation, and thereby offers the potential to double the cooling effect for a given unit air consumption. The overall effects reduce energy costs significantly. The vortex tube 10 of the present disclosure uses only compressed air and no ozone depleting chemicals, not even new ozone safe chemicals that can be flammable. There is the potential for improved safety and efficiency in industry and is better for the environment.
In some embodiments, the cold end 14 is configured to receive a cold end muffler and loc-line style or other hose/tubing/piping to transmit and deliver the cold air produced. The less any hot air exhausted from any single or combination of the previous aspects, allows the cold air exhaust to work against larger back pressures. Previous designs of vortex tubes allowed the vortex tube to work against a maximum pressure of approximate 5 inches of water. According the present disclosure, the vortex tube 10 has been tested against a back pressure of 30 inches of water with still significant cooling, because so little air needs to be exhausted from the hot end 12. In some aspects, the amount of hot end exhaust can be reduced from 80% to 40% of total air consumed for the same, coldest cold end temperature generated. In some other aspects, a maximum of 10% of hot end exhaust only needs to be exhausted. Consequently, the increased cold end flow is much less sensitive to back pressure, and cooling efficiency greatly improved as cooling is proportional to the flow at the cold end 14, and the temperature drop.
In some embodiments, the hot end 12 is configured to receive a hot end muffler.
According to an embodiment and with reference to FIGS. 15a to 15d , there is provided an end plug 340 that can be secured to the vortex tube 10 and a hot end air release system that allows the hot end waste air to blow back down over the hot end 12 of the vortex tube 10. End plug 340 is secured at the end of the hot end tube 34 and is configured so that it is able to control the velocity and the cooling with minimal energy loss and reduces restrictions in the generation of the cold toroidal (spinning) gas. The end plug 340 comprises a body 342, a cap 344 defining an outer perimeter 346, and a lower portion 348.
Lower portion 348 includes a conical tip 349 that comprises a particular angle range to minimize energy losses that varies from about 30 degrees to about 75 degrees. In aspects, the conical angle can vary from 45 degrees to 60 degrees. The plug 340 can be secured to the sidewall of the tube 10 at the hot end 12 with its conical tip 349 pointed towards the cold end 14. The conical tip 349 is configured to direct any hot air (i.e. a first working fluid) to the sidewalls of the tube 10 and up and through the body 342 of the plug 340 and colder air towards the cold end 14.
Plug 340 defines a plurality of exhaust passages 350 through the plug 240 where the channels 350 are configured to flow the first working fluid up through the body 342. In one aspect, the passages 350 include an inlet 352 arranged so that the first working fluid enters into the body 342 at an angle perpendicular to the longitudinal axis of the tube 10.
As shown in FIGS. 15b, 15c, and 15d , the first working fluid travels up through the body 342 and exits the body 342 through one or more exhaust ports 360 which are arranged to direct the first working fluid out and away from the tube and, in some embodiments, in a direction that is substantially perpendicular to the central longitudinal axis of the tube 10.
In aspects, the end plug 340 is threadably secured to the vortex tube 10 via more or more threads 370 which cooperate with mutually engaging threads (not shown) disposed on the wall of the tube 10. End plug 340 is axially moveable by tightening or loosening the plug 340 in relation to the vortex tube 10 to adjust the diameter of the exhaust ports 360.
One or more seals 372 between the interior of the tube 10 and the plug 340 are provided to seal the interior of the tube from the outside.
According to another embodiment and with reference to FIGS. 15b, 16a, 16b , there is provided a vortex generator 320 having sidewalls 322 which are contoured with an concave shape so that chamber 24—which surrounds the sidewalls 322—is provided with a larger interior volume for chamber 24.
The embodiments of the present application described above are intended to be examples only. Those of skill in the art may effect alterations, modifications and variations to the particular embodiments without departing from the intended scope of the present application. In particular, features from one or more of the above-described embodiments may be selected to create alternate embodiments comprised of a subcombination of features which may not be explicitly described above. In addition, features from one or more of the above-described embodiments may be selected and combined to create alternate embodiments comprised of a combination of features which may not be explicitly described above. Features suitable for such combinations and subcombinations would be readily apparent to persons skilled in the art upon review of the present application as a whole. Any dimensions provided in the drawings are provided for illustrative purposes only and are not intended to be limiting on the scope of the invention. The subject matter described herein and in the recited claims intends to cover and embrace all suitable changes in technology.

Claims

1.-85. (canceled)

86. A vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising:

a hot end;

a cold end opposed to the hot end;

a vortex generator between the hot end and the cold end, the vortex generator configured to receive a working fluid, the vortex generator including a bottom wall defining a bore therethrough and configured to direct the working fluid in a vortex motion to form a first toroidal moving away from the vortex chamber and towards the hot end;

an end plug coupled to the hot end of the vortex tube, the end plug comprising:

a body, the body comprises a lower portion configured to separate the working fluid into the first working fluid and allow the exit of the first working fluid from the vortex tube through an exit aperture formed between the body and the wall of the vortex tube and into the second working fluid and direct the second working fluid away from the hot end and towards the cold end;

wherein the body further comprises cap with an outer perimeter having a contoured surface configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube and to cling to outer wall of the vortex tube and thereby reducing the temperature of the hot end of the vortex tube.

87. The vortex tube of claim 86 where the contoured surface forms an angle of about 45 degrees from the horizontal.

88. The vortex tube of claim 86 further comprising a heat sink disposed at the hot end, the heat sink comprising a plurality of spaced apart fins disposed along the wall at the hot end and configured to dissipate thermal energy generated within the interior of the vortex tube away from the wall.

89. The vortex tube of claim 88 wherein the plurality of spaced-apart fins extend outwardly about the longitudinal center of the vortex tube.

90. The vortex tube of claim 88 wherein each of one the plurality of spaced-apart fins comprises a contoured surface configured to flow the combined air away from the hot end and towards the cold end.

91. The vortex tube of claim 90 where the contoured surface is a rounded surface.

92. The vortex tube of claim 91 wherein the contoured surface of an end fin adjacent to the end of the hot end defines a second contoured surface that is co-linear with the contoured surface of the cap and is configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube.

93. The vortex tube of claim 86 wherein the interior wall at the hot end defines a plurality of circumferentially disposed slots for channeling the first working fluid between the lower portion and the wall of the vortex tube.

94. The vortex tube of claim 93 wherein the plurality of circumferentially disposed slots are sem i-circular.

95. The vortex tube of claim 93 wherein the thickness of the interior wall at the hot end along the length of plurality of circumferentially disposed slots is sufficiently thin to promote dissipation of thermal energy.

96. The vortex tube of claim 93 wherein the width and/or length of the plurality of circumferentially disposed slots is dimensioned to maximize a rate of flow of the first working fluid while maintaining a sufficient transfer of thermal energy into the wall such that the first working fluid exiting the vortex tube has a reduced thermal energy.

97. The vortex tube of any 93 wherein the first working fluid exiting the plurality of circumferentially disposed slots enter into a chamber having outwardly flaring walls for drawing the first working fluid out of the vortex tube.

98. A vortex tube for separating a working fluid into a first working fluid and a second working fluid, the vortex tube comprising:

a hot end;

a cold end opposed to the hot end;

and an end plug coupled to the hot end of the vortex tube, the end plug comprising:

a body, the body comprises a lower portion configured to separate the working fluid into the first working fluid and allow the exit of the first working fluid from the vortex tube through an exit aperture formed between the body and the wall of the vortex tube and into the second working fluid and direct the second working fluid away from the hot end and flows through the bore to exit the cold end; wherein the interior wall at the hot end defines a plurality of circumferentially disposed slots for channeling the first working fluid between the lower portion and the wall of the vortex tube.

99. The vortex tube of claim 98 wherein the lower portion terminates at a conical tip.

100. The vortex tube of claim 99 wherein the conical tip includes a conical angle from about 30 degrees to about 75 degrees for generating a second toroidal motion and causing the second working fluid to move away from the hot end towards the cold end.

101. The vortex tube of claim 100 wherein the conical angle is from about 45 degrees to about 60 degrees.

102. The vortex tube of claim 100 wherein the second toroidal motion comprises a laminar flow.

103. The vortex tube of claim 98 wherein the plurality of circumferentially disposed slots are sem i-circular.

104. The vortex tube of claim 98 wherein the thickness of the interior wall at the hot end along the length of plurality of circumferentially disposed slots is thin to promote dissipation of thermal energy.

105. The vortex tube of claim 98 wherein the width and/or length of the plurality of circumferentially disposed slots is dimensioned to maximize a rate of flow of the first working fluid while maintaining a sufficient transfer of thermal energy into the wall such that the first working fluid exiting the vortex tube has a reduced thermal energy.

106. The vortex tube of claim 98 wherein the first working fluid exiting the plurality of circumferentially disposed slots enters into a chamber having outwardly flaring walls for drawing the first working fluid out of the vortex tube.

107. The vortex tube of any claim 98 wherein the body further comprises cap with an outer perimeter having a contoured surface configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube and to cling to outer wall of the vortex tube and thereby reducing the temperature of the hot end of the vortex tube.

108. The vortex tube of claim 107 where the contoured surface forms an angle of about 45 degrees from the horizontal.

109. The vortex tube of claim 98 further comprising a heat sink disposed at the hot end, the heat sink comprising a plurality of spaced apart fins disposed along the wall at the hot end and configured to dissipate thermal energy generated within the interior of the vortex tube away from the wall.

110. The vortex tube of claim 109 wherein the plurality of spaced-apart fins extend outwardly about the longitudinal center of the vortex tube.

111. The vortex tube of claim 109 wherein each of one the plurality of spaced-apart fins comprises a contoured surface configured to flow the combined air away from the hot end and towards the cold end.

112. The vortex tube of claim 111 where the contoured surface is a rounded surface.

113. The vortex tube of claim 111 wherein the contoured surface of an end fin adjacent to the end of the hot end defines a second contoured surface that is co-linear with the contoured surface of the cap and is configured to draw air surrounding the vortex tube for mixing with the first working fluid exiting from the vortex tube.