Air outlet device
10639653 ยท 2020-05-05
Assignee
Inventors
Cpc classification
B05B1/048
PERFORMING OPERATIONS; TRANSPORTING
B05B1/044
PERFORMING OPERATIONS; TRANSPORTING
F26B21/004
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
International classification
B05B1/04
PERFORMING OPERATIONS; TRANSPORTING
F26B21/00
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
Abstract
An air outlet device is disclosed herein. The air outlet device includes a plenum body portion, the plenum body portion defining an air chamber therein, the plenum body portion including an air inlet configured to be coupled to a supply air source for supplying air to the air chamber; an air nozzle portion fluidly coupled to the plenum body portion and including a nozzle inlet and an exit orifice, the air nozzle portion configured to discharge the air from the air chamber at a substantially uniform velocity through the exit orifice; and an air nozzle extension fluidly coupling the air chamber of the plenum body portion to the nozzle inlet of the air nozzle portion, the air nozzle extension being configured to increase an efficiency of the air outlet device by decreasing the pressure drop that occurs when the pressure energy of the air is converted to kinetic energy.
Claims
1. An air outlet device, comprising: a plenum body portion, said plenum body portion defining an air chamber therein, said plenum body portion including an air inlet configured to be coupled to a supply air source for supplying air to said air chamber; an air nozzle portion fluidly coupled to said plenum body portion, said air nozzle portion including a nozzle inlet and an exit orifice, said air nozzle portion configured to discharge said air from said air chamber at a substantially uniform velocity through said exit orifice; and an air nozzle extension fluidly coupling said air chamber of said plenum body portion to said nozzle inlet of said air nozzle portion, said air nozzle extension being configured to increase an efficiency of said air outlet device by decreasing the pressure drop that occurs when the pressure energy of said air is converted to kinetic energy; wherein said air nozzle portion comprises a substantially straight wall section fluidly coupled to said air nozzle extension and a tapered wall section disposed downstream of said substantially straight wall section, said tapered wall section of said air nozzle portion comprising said exit orifice at a downstream end thereof.
2. The air outlet device according to claim 1, wherein said air nozzle extension is internally disposed within said air outlet device so as to not result in an increased height of said air outlet device beyond that which is required to accommodate said plenum body portion and said air nozzle portion.
3. The air outlet device according to claim 2, wherein said air nozzle extension comprises a curved wall section fluidly coupled to said air chamber of said plenum body portion and a straight wall section disposed downstream of said curved wall section, said straight wall section being fluidly coupled to said nozzle inlet of said air nozzle portion.
4. The air outlet device according to claim 3, wherein said curved wall section and said straight wall section of said air nozzle extension project into said air chamber of said plenum body portion.
5. The air outlet device according to claim 3, wherein a radius of said curved wall section of said air nozzle extension is substantially greater than a width of said nozzle inlet.
6. The air outlet device according to claim 1, wherein said air nozzle extension comprises a curved wall section attached to a wall portion of said plenum body portion.
7. The air outlet device according to claim 6, wherein a radius of said curved wall section of said air nozzle extension is substantially greater than a width of said nozzle inlet.
8. The air outlet device according to claim 1, wherein said plenum body portion is elongate with a length that is substantially greater than a width or a height thereof.
9. The air outlet device according to claim 1, wherein said plenum body portion has a first end and a second end oppositely disposed relative to said first end, and wherein said plenum body portion comprises one or more inlet collars disposed at respective ones of said first and second ends, said one or more inlet collars defining said air inlet of said plenum body portion, and said one or more inlet collars configured to connect to an air supply line.
10. The air outlet device according to claim 1, wherein said plenum body portion has a circular, elliptical, or polygonal cross-sectional shape.
11. An air outlet device, comprising: a plenum body portion, said plenum body portion defining an air chamber therein, said plenum body portion including an air inlet configured to be coupled to a supply air source for supplying air to said air chamber; an air nozzle portion fluidly coupled to said plenum body portion, said air nozzle portion including a nozzle inlet and an exit orifice, said air nozzle portion configured to discharge said air from said air chamber at a substantially uniform velocity through said exit orifice; and an air nozzle extension fluidly coupling said air chamber of said plenum body portion to said nozzle inlet of said air nozzle portion, said air nozzle extension being internally disposed within said air outlet device so as to not result in an increased height of said air outlet device beyond that which is required to accommodate said plenum body portion and said air nozzle portion, said air nozzle extension being configured to increase an efficiency of said air outlet device by decreasing the pressure drop that occurs when the pressure energy of said air is converted to kinetic energy; wherein said air nozzle portion comprises a substantially straight wall section fluidly coupled to said air nozzle extension and a tapered wall section disposed downstream of said substantially straight wall section, said tapered wall section of said air nozzle portion comprising said exit orifice at a downstream end thereof.
12. The air outlet device according to claim 11, wherein said air nozzle extension comprises a curved wall section fluidly coupled to said air chamber of said plenum body portion and a straight wall section disposed downstream of said curved wall section, said straight wall section being fluidly coupled to said nozzle inlet of said air nozzle portion.
13. The air outlet device according to claim 12, wherein said curved wall section and said straight wall section of said air nozzle extension project into said air chamber of said plenum body portion.
14. The air outlet device according to claim 12, wherein a radius of said curved wall section of said air nozzle extension is substantially greater than a width of said nozzle inlet.
15. The air outlet device according to claim 11, wherein said air nozzle extension comprises a curved wall section attached to a wall portion of said plenum body portion.
16. The air outlet device according to claim 15, wherein a radius of said curved wall section of said air nozzle extension is substantially greater than a width of said nozzle inlet.
17. The air outlet device according to claim 11, wherein said plenum body portion is elongate with a length that is substantially greater than a width or a height thereof.
18. The air outlet device according to claim 11, wherein said plenum body portion has a first end and a second end oppositely disposed relative to said first end, and wherein said plenum body portion comprises one or more inlet collars disposed at respective ones of said first and second ends, said one or more inlet collars defining said air inlet of said plenum body portion, and said one or more inlet collars configured to connect to an air supply line.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
(1) The invention will now be described, by way of example, with reference to the accompanying drawings, in which:
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(16) Throughout the figures, the same parts are always denoted using the same reference characters so that, as a general rule, they will only be described once.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
(17) A first illustrative embodiment of an air outlet device is seen generally at 10 in
(18) Now, with particular reference to
(19) Also, as best shown in
(20) Next, referring to
(21) Now, with combined reference to
(22)
Also, in the illustrative embodiment, as shown by the following equation, the ratio of the width D of the nozzle inlet to the overall height H of the air outlet device 10 (i.e., the D/H ratio) may be between 0.10 and 0.25 in order to maximize the efficiency of the air outlet device 10, while maintaining a compact design:
(23)
Further, the pressure p.sub.1 in the air chamber 26 of the plenum body portion 12 of the air outlet device 10 is given by the following equation:
p.sub.1=C.sub.0*p.sub.vel(3)
(24) where: C.sub.0 is the discharge coefficient for the air outlet device 10; and p.sub.vel is the discharge velocity of the air outlet device 10.
The following table gives discharge coefficient values that correspond to various values of the ratio of the radius R of the curved wall section 22 of the air nozzle extension 20 to the width D of the nozzle inlet (i.e., the R/D ratio):
(25) TABLE-US-00001 TABLE 1 Discharge Coefficient Values For Various R/D Ratio Values (First Embodiment) R/D C.sub.0 R/D C.sub.0 0 0.5 0.06 0.20 0.01 0.44 0.08 0.15 0.02 0.37 0.10 0.12 0.03 0.31 0.12 0.09 0.04 0.26 0.16 0.06 0.05 0.22 0.20 0.03
As shown in Table 1 above, the discharge coefficient C.sub.0 continually decreases as the R/D ratio for the air outlet device 10 increases until reaching an R/D ratio of 0.20. For R/D ratios exceeding 0.20, the discharge coefficient C.sub.0 only decreases very slightly. As such, in the illustrative embodiment, the air outlet device 10 has an R/D ratio of at least 0.20 in order to minimize the discharge coefficient C.sub.0 of the air outlet device 10, thereby maximizing the discharge velocity of the air outlet device 10.
(26) A second illustrative embodiment of the air outlet device is seen generally at 50 in
(27) Like the air outlet device 10 described above, the air outlet device 50 of the second illustrative embodiment generally comprises (i) a plenum body portion 52 (see e.g.,
(28) Now, with particular reference to
(29) Also, as best shown in
(30) Next, referring to
(31) Now, with combined reference to
(32)
Also, in the illustrative embodiment, as shown by the following equation, the ratio of the width D of the nozzle inlet to the overall height H of the air outlet device 50 (i.e., the D/H ratio) may be between 0.10 and 0.25 in order to maximize the efficiency of the air outlet device 50, while maintaining a compact design:
(33)
Further, the pressure p.sub.1 in the air chamber 66 of the plenum body portion 52 of the air outlet device 50 is given by the following equation:
p.sub.1=C.sub.0*p.sub.vel(6)
(34) where: C.sub.0 is the discharge coefficient for the air outlet device 50; and p.sub.vel is the discharge velocity of the air outlet device 50.
The following table gives discharge coefficient values that correspond to various values of the ratio of the radius R of the curved wall 62 of the air nozzle extension 60 to the width D of the nozzle inlet (i.e., the R/D ratio):
(35) TABLE-US-00002 TABLE 2 Discharge Coefficient Values For Various R/D Ratio Values (Second Embodiment) R/D C.sub.0 R/D C.sub.0 0 0.5 0.06 0.20 0.01 0.44 0.08 0.15 0.02 0.37 0.10 0.12 0.03 0.31 0.12 0.09 0.04 0.26 0.16 0.06 0.05 0.22 0.20 0.03
(36) As shown in Table 2 above, the discharge coefficient C.sub.0 continually decreases as the R/D ratio for the air outlet device 50 increases until reaching an R/D ratio of 0.20. For R/D ratios exceeding 0.20, the discharge coefficient C.sub.0 only decreases very slightly. As such, in the illustrative embodiment, the air outlet device 50 has an R/D ratio of at least 0.20 in order to minimize the discharge coefficient C.sub.0 of the air outlet device 50, thereby maximizing the discharge velocity of the air outlet device 50.
(37) Now, the functionality of the air outlet device 10, 50 described above will be explained. In the illustrated embodiments of the air outlet device 10, 50 described above, the compressed air is introduced into the air chamber 26, 66 of the plenum body portion 12, 52 of the air outlet device 10, 50 through the inlet opening 28, 68 at the second end 12b, 52b of the plenum body portion 12, 52. In alternative embodiments, the compressed air may be introduced into the air chamber 26, 66 of the plenum body portion 12, 52 from both ends of the plenum body portion 12, 52. The exit orifice 30, 70 on the bottom of this plenum body portion 12, 52, which is in the form of a small gap, extends along the length of the air outlet device 10, 50 and allows the air to escape from the orifice 30, 70. The air escaping from the orifice 30, 70 escapes in a radial direction from the air outlet device 10, 50 in a thin, uniform, high velocity jet. The width of the orifice 30, 70 is substantially smaller than the size of the plenum body portion 12, 52. This small orifice size creates a substantial pressure drop, which helps create a uniform velocity along the length of the orifice 30, 70. If this orifice 30, 70 is made too large, the pressure drop is reduced, but the velocity varies along the length of the gap which results in a highly uneven jet. Uneven jet velocity from air outlet device 10, 50 can create unwanted variations in the drying or cooling rate of products and, as a result, is undesirable. At the same time, very small orifice sizes create uniform jet velocities but they create high pressure drops. These high pressure drops result in the use of high pressure compressors and high operating costs. In the illustrated embodiments, the width of the nozzle exit orifice 30, 70 of the air outlet device 10, 50 may be between 0.10 inches and 0.12 inches in order to create a substantially uniform velocity along the length of the orifice 30, 70 without an excessively highly pressure drop.
(38) The air outlet device 10, 50 described above utilizes the inventive internal nozzle extension 20, 60 to improve air knife efficiency, while maintaining the compact size (e.g., a height of 10 inches or less) that is necessary for industrial applications. By virtue of the inventive internal nozzle extension 20, 60, the air outlet device 10, 50 efficiently converts pressure energy to kinetic energy so to achieve a highly uniform jet with substantially reduced pressure drops, thus providing a continuous drying or cooling function with minimum power requirements.
(39) It is readily apparent that the aforedescribed air outlet device 10, 50 offers numerous advantages. First, the air outlet device 10, 50 has a higher efficiency than conventional devices so that the power consumption of the air outlet device is significantly reduced. Secondly, the aforedescribed air outlet device 10, 50 is capable of operating at a higher efficiency, while still remaining compact so as to satisfy system space constraints. Finally, the air outlet device 10, 50 described herein is capable of producing highly uniform air jets with substantially reduced pressure drops.
(40) Advantageously, the air outlet device 10, 50 described herein is compact and more efficient than conventional devices so that it is able to function with lower power consumption in a compact format. In the illustrative embodiment, the air outlet device 10, 50 is designed for optimum performance at medium low pressure (i.e., 3 to 5 psig). This is the ideal pressure range for high efficiency, low pressure air compressors and further reduces the power required for a specific air knife application. Also, advantageously, the aforedescribed air outlet device 10, 50 produces a higher air thrust at design pressure due to its unique internal design and construction.
(41) Although the invention has been shown and described with respect to a certain embodiment or embodiments, it is apparent that this invention can be embodied in many different forms and that many other modifications and variations are possible without departing from the spirit and scope of this invention.
(42) Moreover, while exemplary embodiments have been described herein, one of ordinary skill in the art will readily appreciate that the exemplary embodiments set forth above are merely illustrative in nature and should not be construed as to limit the claims in any manner. Rather, the scope of the invention is defined only by the appended claims and their equivalents, and not, by the preceding description.