JPH03504824A - Noise damping supersonic nozzle - Google Patents

Abstract

A sound attenuating supersonic nozzle (1) has an exit (9) to throat (8) ratio in the range of 2.5 to 6.0, with longitudinal grooves (17) formed in the interior wall of the supersonic passageway (6) of the nozzle body (2). A shield is disposed about the exterior surface of the nozzle body, forming an exit cavity and an exit opening, and has gill cavity through which auxiliary air flows into the exit cavity and mixes with the supersonic flow.

Description

[Detailed description of the invention] TECHNICAL FIELD This invention relates generally to supersonic nozzles, and more particularly to supersonic nozzles during operation. Concerning attenuating emitted noise. The present invention relates to, inter alia, specific scope The internal characteristics of the supersonic passage and the emitted noise supersonic nozzles having an external shape of the nozzle body that tends to attenuate the will be specifically disclosed.

Background of the invention Supersonic nozzles are well known in the art.

A conventional converging-diverging nozzle includes a converging zone, a throat, and a widening zone. I'm here. If sufficient pressure is applied to the converging-diverging nozzle, the air in the throat The velocity becomes the speed of sound, where it increases as the air expands in the expansion zone until it reaches supersonic speed. Produces mouth velocity. The exact exit velocity depends on air pressure, size and other nozzle design details. Depends on.

Nozzles can be used for various purposes. They are kept at a certain distance from the operator and other people. can be automatically activated at a remote location. Other nozzles can be held by the operator. and allows the operator to direct the outflow to achieve a specific objective.

One particular use of such a nozzle is disclosed in U.S. Pat. No. 4.744.181. In combination with a particle blast cleaning device as shown. This kind of The slurry typically consists of a carrier gas flowing at supersonic speeds and a diacid carried by the carrier gas. hand-held type by an operator who directs a stream consisting of a mixture of carbonized pellets belongs to. The flow is carried out by particle blasting or coolant particle blast cleaning methods. is directed onto the object to be cleaned.

The main problem with the use of supersonic nozzles is the decimals emitted by the nozzle during operation. It is a bell level noise.

Such noise can be caused by the capacity of certain nozzle designs when close proximity is required. This is a critical factor in recognition and use. In addition, such a nozzle When used in an enclosed area such as a factory, reflective surfaces in this area Surfaces tend to increase the decibel level experienced at a particular location.

The sound pressure level (dBA) of 120 dB in A scale is human by 05HA. This was determined to be the threshold level of pain for the patient. However, professional situations In the 05HA, the level of human exposure to such noise for an 8-hour period was The signal is limited to less than 90 dBA.

Industrial and US military standards set this level at 85 dBA.

Typical prior art nozzles, such as those used in particle blast cleaning equipment, It has been measured that a noise as high as 130 dBA is emitted at the position of . Special The nozzle disclosed in U.S. Pat. No. 4,038,786 has a 127 dBA nozzle. Reported to emit a range of noise. Since the dB scale is logarithmic, , a change of 3 decibels represents twice the sound pressure level. Therefore, the pain of 08HA The difference between the 120 dBA limit level and the 127 dBA of a typical prior art nozzle is: This shows a more than 4-fold increase in sound pressure level. 0SHA limit 90dBA By comparison, this difference is more than a 4.000 times increase in sound pressure level of 90 dBA.

Compared to the industrial and US military standard of 85 dBA, typical prior art nozzles The 127dBA level has a sound pressure level that is 16,000 times more than this standard. .

As is clear, the sound emitted by the supersonic nozzle is capable of safe continuous operation. must be reduced to as low a level as possible. Is it possible to protect the ears? However, such protection devices attenuate noise by a range of 20-25 dBA.

This means that a typical 127 dBA prior art nozzle would be 102 dBA at the operator's location. This would result in a sound pressure level as low as BA. This is experienced by the operator 0S for an 8 hour exposure, although significantly reducing sound pressure levels Exceeds the limits of HA, industrial and military standards.

Furthermore, in a factory setting, unrelated personnel in the vicinity of supersonic nozzle use may It is unrealistic to require workers to wear such ear protection devices. Ultimate The objective and solution is to ensure that operators wearing approved ear protection equipment are exposed to 8 It is recommended to use supersonic nozzles with sufficiently low sound pressure levels of less than 5 dBA. Ru. Such a nozzle has a sound pressure level below 115 (IBA) at the operator's location. should have a file. The 115 dBA level is 15 dBA from the nozzle you are operating. It may also be acceptable for workers not wearing ear protection who are more than one foot away.

Summary of the invention Therefore, the primary object of the present invention is to provide a 115 dB The present invention relates to a supersonic nozzle that emits noise having a sound pressure level of less than A. Ru.

Another object of the invention is to prevent the shock waves associated with such supersonic flow from exiting the nozzle before exiting the passage. An object of the present invention is to provide a supersonic nozzle formed within a supersonic passage of a fuel cell.

Yet another object of the invention is to prevent the coalescence of shock waves generated by supersonic flows. The purpose of the present invention is to provide a supersonic nozzle that can achieve the desired speed.

Yet another object of the invention is to provide 0SHA, industrial and Consistent with U.S. military standards, workers who are not required to wear ear protection The purpose of the present invention is to provide a supersonic nozzle that can be used even when

Other objects, advantages, and other novel features of the invention are disclosed in part in the description below. and some of which will be apparent to those skilled in the art from the following discussion, or can be learned by practicing the present invention. The objects and advantages of the invention are attached realized by means of the devices and combinations particularly pointed out in the claims. can get.

To achieve the above and other objects, and to the objects of the invention herein described, Thus, having a passage formed in the nozzle body having an inlet, a throat, and an outlet. An improved supersonic nozzle is provided. Ratio of exit area to throat area is in the range 2.5 to 6.0, so that the static pressure of the supersonic flow at the exit is lower than ambient static pressure.

According to yet another aspect of the invention, a plurality of longitudinal grooves are provided adjacent the inner wall of the supersonic passageway. formed in contact with and adjacent to the outlet.

According to yet another aspect of the invention, the groove is arranged inwardly in the passageway from the outlet to the throat. It extends along its length to a point where the static pressure of the flow is equal to the ambient static pressure.

According to yet another aspect of the invention, the supersonic path is formed by two sets of opposing surfaces. has an elongated rectangular cross section, and the longitudinal grooves are formed in a pair of opposing surfaces. Ru.

In yet another aspect of the invention, the nozzle inlet exceeds the flow of compressible fluid. It is connected to a nozzle body having an inlet passageway feeding into the sonic passageway. The entrance passage is the entrance It has a circular cross section at its outlet and a rectangular cross section at its outlet.

According to yet another aspect of the invention, a number of recesses are formed in the outer surface of the nozzle body. Ru. According to a subsequent aspect of the invention, the recess has multiple inserts made of different materials. can be filled.

According to yet another aspect of the invention, the recess is formed longitudinally in the outer surface of the nozzle body. made of metal and has a greater density than the material of which the nozzle body is formed. Inserts can be filled.

According to yet another aspect of the invention, the supersonic path of the nozzle is in the range of 2.5 to 6.0. having a ratio of exit area to throat area that is also similarly formed into a supersonic passageway. a large number of longitudinal ribs formed on the outer surface of the nozzle body; It has a number of inserts placed in recesses in the direction.

According to yet another aspect of the invention, a shielding material is disposed around the outer surface of the nozzle body. an outlet aperture located in the supersonic passageway extending in the flow direction beyond the outlet and aligned with the outlet of the supersonic passageway; is formed. The exit opening is at least as large as the exit cross-sectional area of the supersonic passage. It has a cross-sectional area.

According to yet another aspect of the invention, the exit opening is smaller than the exit opening of the supersonic passage. At least 25% larger.

According to yet another aspect of the invention, the auxiliary air flow exits through the outlet opening. Means are provided for forcing auxiliary air into the outlet cavity.

Furthermore, according to another aspect of the present invention, the gap is between the outer surface of the nozzle body and the shield material. formed between.

According to yet another aspect of the invention, between the outer surface of the nozzle body and the periphery of the outlet opening; The angle formed is at least 60 degrees.

According to yet another aspect of the invention, the shielding material may be any part of the outer surface of the nozzle body. Do not come into direct contact with any parts.

Yet another object of the invention is to provide, by way of example only, The following description illustrates and describes preferred embodiments of the invention, which are considered to be the best aspects. will be clear to those skilled in the art. It will be appreciated that the invention may be applied to other Other embodiments are possible, and certain details may be modified in various ways without departing from the invention. It is deformable in its bright aspects. Accordingly, the drawings and description are purely illustrative. It should be understood that the The accompanying drawings illustrate some aspects of the invention and, together with the description, provide a detailed description of the invention. Serve for explanation. In the drawings: FIG. 1 shows a first embodiment of a supersonic nozzle. FIG.

FIG. 2 is an end view along line A of FIG. 1 showing the exit of the supersonic nozzle.

Figure 3 shows the supersonic passageway and its shape and the formation adjacent to the exit of the supersonic passageway. FIG. 3 is a cross-sectional view taken along line 3-3 of FIG. 2 showing the longitudinal ribs that have been removed;

Figure 4 is viewed from line 4-4 in Figure 3, which shows one mating part of the nozzle body with imaginary lines. FIG. 3 is a cross-sectional view of the throat of the supersonic passage.

FIG. FIG. 3 is a perspective view of a second embodiment of a supersonic nozzle with a oriented insert;

Figure 6 shows a supersonic nozzle with shielding material placed around the outer surface of the nozzle body. FIG. 6 is a perspective view of a third embodiment of the Zulu;

FIG. 7 is an exploded perspective view of the supersonic nozzle and shield material of FIG. 6.

FIG. 8 is a side view of a portion of the shield material of FIG. 6.

FIG. 9 is an end view of the shield material of FIG. 8.

FIG. 10 is a plan view of a portion of the shield material of FIG. 6.

FIG. 11 shows a shielding material section showing an assembly of the nozzle and shielding material of FIG. 6. FIG.

FIG. 12 is a partial cross-sectional end view of the nozzle of FIG. 6 showing the outlet opening and nozzle exit; It is.

FIG. 13 is a perspective view showing a fourth embodiment of the supersonic nozzle.

FIG. 14 is a perspective view of a fifth embodiment showing a supersonic nozzle with a circular outlet; .

Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. I will explain.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, FIG. 1 shows an overall construction constructed in accordance with the present invention. 1 shows a supersonic nozzle designated by numeral 1; The nozzle body 2 has an upper part 3 and a lower part are shown formed with portions 4, which include a number of fasteners such as bolts 5. held together by. Briefly referring to FIG. 3, the supersonic passage 6 is located in the upper part. 3 and the lower part 4, and as shown in the outline, the lower entrance and throw It has an outlet 8 and an outlet 9. Returning to FIG. 1, the nozzle inlet 10 is secured by a bolt 11. is connected to the nozzle body 2. A passage (not shown) is inside the nozzle population 10. One end of the nozzle inlet communicates with the lower inlet, and the other end communicates with the lower inlet. 12 is connectable to receive the flow of compressible fluid. a pair of distances A groove 13 , 14 is formed around the circumference of the nozzle inlet 10 near the end 12 . Ru.

Referring to FIG. 2, which is an end view of the nozzle 1, the outer surface 15 of the nozzle body 2 is entirely It can be seen that it is continuous.

The passageway 6 and the outlet 9 are shown as having an elongated rectangular cross-sectional shape. original Generally speaking, an elongated rectangle has dimensions in one direction that are equal to dimensions in the other direction, as depicted here. substantially larger than. The rectangle is formed by the inner wall 16 of the supersonic passage 6.

Although the supersonic passage 6 is shown as having an elongated rectangular cross section, as will be described later, it has a circular cross section. It may be a shape. Regardless of the shape, the elongated rectangular or circular supersonic passage 6 is , in an elongated rectangular cross-sectional shape as shown in FIG. Although there are 16c and 16d, it is considered to have one inner wall 16. figure As shown, the rectangular cross section has two sets of opposing surfaces 16a-16c and 16b-16d. It can be thought of as consisting of

A large number of grooves 17 are formed in a pair of opposing surfaces 16b and 16d of the inner wall 16. ing. Groove 17 is shown at outlet 9 in FIG. 3 as it actually begins at outlet 9. Shown adjacent. In reality, the groove 17 does not actually extend from the outlet 9. or it can be formed at a short distance upstream of the outlet 9. groove 17 extends inwardly from outlet 9 towards throat 8 along the length of passageway 6 to point 18. It is growing. As shown, groove 17 is a series of depressions along inner walls 16b and 16d. It is formed as a groove 17a and a protrusion 17b.

Referring again to FIG. A fast path 6 is shown. An enlarged area 19a is shown from the throat 8 to the outlet 9. Ru.

FIG. 4 shows a cross section showing its rectangular shape as seen through the throat 8, and This shows that point 8 has a smaller cross-sectional area than any other location in supersonic path 6.

In operation, the end 12 of the nozzle inlet 10 delivers a continuous stream of compressible fluid. Connected to a flexible hose (not shown). Well understood in our industry Similarly, compressible fluids are gases that are accelerated to supersonic flow through a converging-diverging nozzle. It can be done. Grooves 13 and 14 are attached to hoses carrying a flow of compressible fluid. The receptacle is configured to be received by a rapid separation mechanism (not shown).

In this embodiment of the invention, the air has a circular cross-section at the end 12 of the nozzle population 10. flows through. The internal cavity (not shown) of the nozzle inlet 10 is the entrance of the supersonic passage 6. It changes from a circular cross section to a rectangular cross section along the length of the nozzle inlet 10 that is engaged with the lower. Ru. Air flows through convergence zone 19 and is accelerated to a sonic flow at throat 8 . The flow downstream from throat 8, the sonic flow, expands according to the well-known laws of physics. It is accelerated to supersonic speed as it flows through zone 19a and passes through outlet 9 to nozzle 1. leave.

In supersonic nozzles that maximize the flow moment, the static pressure of the flow at the exit is equal to Opslg, or in other words equal to the ambient (environmental) static pressure. cormorant. Nozzles with low static pressure at outlet 9 are said to be over-expanded-underdeveloped nozzles.

In such overexpansion nozzles, the static pressure of the flow is Ops at a point upstream of the outlet. Reach ig. This is done in terms of maximizing the moment of the flow exiting the nozzle. This will reduce the efficiency of the nozzle.

In such a supersonic flow, at the point where the static pressure of the flow is equal to Opslg A shock wave like the one given here is formed. Greater than OpsIg static pressure at exit For nozzles with high static pressure, a shock wave is formed outside the exit and the supersonic path It is transmitted from It is these shock waves that produce the high sound pressure levels of supersonic nozzles during operation. It is.

This embodiment of the invention allows the supersonic nozzle 1 to emit light by over-inflating the nozzle. reduce the noise generated. Therefore, as shown in FIG. 3, the supersonic nozzle 1 is The flow through reaches Opsig static pressure at location 18. Shock waves are formed by At this point in the supersonic passage 6. The shock wave goes around from position 19 through exit 9. It is attenuated as it travels out into the surrounding environment. Therefore, by this design Noise level is reduced.

The point at which Opsig static pressure is achieved in supersonic flow is relative to the cross-sectional area of throat 8. is determined by the exit/throat ratio, which is the ratio of the cross-sectional area of the exit 9. etc. In a tropic flow (zero losses), a ratio of 2.77 would theoretically result in ops at the exit. tg static pressure is reached. Since ideal flow (zero loss) is unattainable, opstg The actual ratio that produces static pressure is actually less than 2.77. Empirically, 2.4 It was determined that an outlet/throat ratio of 8 would produce a static pressure of Opslg at the outlet. . Therefore, in order to generate a shock wave inside the supersonic passage 6, , an exit/throat ratio of 2.5 or greater is required. In practice, the inventors have determined that 6.0 Exit/throat ratios greater than I found it impractical because of my gender.

The generation of shock waves in the supersonic passageway 6 reduces some of the noise of the operation of the supersonic nozzle 1. Other embodiments of the present invention also provide supersonic speeds as described above, while maintaining It includes a groove 17 formed in the outer wall 16 of the passageway 6. This one near exit 9 of supersonic passage 6 The arrangement of these grooves 17 helps prevent shock waves from converging with each other, thereby strengthen and reinforce themselves. The groove 17 is located upstream from the outlet 9 in the supersonic passage 6. shown extending along its length to the point where Opsig static pressure occurs in the flow. There is. If groove 17 were to extend beyond this point, there would be a significant difference in sound attenuation. resulting in some loss in nozzle efficiency without any corresponding gain. Become. This is because the shock wave is not formed upstream of position 18 and therefore Therefore, any portion of the groove 17 extending beyond the location 18 is prevented from combining shock waves. It doesn't work for.

As shown in FIG. It is formed in d. In this embodiment, the distance between the grooves 17 from the protrusion to the protrusion 17b is It operates efficiently when the separation is between 0.030 and 0.050 inches. This distance It is particularly efficient at 0.030 inches. If this distance is too large, the shock wave This reduces the efficiency of the grooves 17 to prevent convergence.

The depth of the groove 17 from the protrusion 17b to the depression 17a is 0.005 to 0.015 inches. within the range of If the groove 17 is too shallow, the groove 17 will be effective in preventing the combination of shock waves. Not on point. If grooves 17 are too deep, they reduce the efficiency of the nozzle.

Referring now to FIG. 5, the supersonic nozzle 1 has a longitudinal has a shape that complements the recess 20g and has a number of inserts 20 arranged therein. It is shown as being possible. As noted, in this embodiment, the insert 20 are arranged on opposing outer surfaces 15b and 15d. insert 20 and The recess 20a extends along the length of the nozzle body 2 and is located at the end 21 of the nozzle body 2. It is shown as being terminated. Insert 20 is similar to outer surface 15 as shown. It may be on one side or may extend above or below the outer surface 15. insert 20 may be a single piece of material per recess 20a, or may be made of several pieces per recess 20a. Several inserts 20 may be stacked.

Although the nozzle body 2 can be made of any suitable material, in this embodiment is made of aluminum. The insert 20 is made of material forming the nozzle body 2. Preferably, it is made of a similar material with a greater density.

In this embodiment, insert 20 is made of lead.

The noise generated by the operation of the supersonic nozzle 1 is also transmitted through the nozzle body 2. , absorbed and then emitted again from the nozzle. Concavities on the outer surface 15 of the nozzle body 2 By arranging the insert 20 at the position 20a, the nozzle body 2 that transmits noise can be Capacity is reduced. By forming a discontinuous shape or recess 20a in the outer surface 15. , resonances at the surface 15 are prevented at some frequencies. The lead insert 20 is Because of the density of lead, it absorbs some of the energy of the sound that is transmitted, thereby reduce sound transmission from surfaces.

The variant embodiment of FIG. 5 forms a recess 20a in the outer surface 15 of the nozzle body 2, and No insert should be placed in the recess 20a. As mentioned above, the outer surface 15 Such discontinuities help reduce the transmission of sound therefrom. But long In addition, as also described above, the voice further fills the recess 20a with the insert 20. It is also reduced by Although longitudinal recesses and inserts are shown as well as randomly sized and randomly placed recesses and inserts. This will result in audio attenuation of . Figure 5 shows a nozzle with a groove 17 in the supersonic passage 6. Although the illustration shows the use of recess 20a and insert 2o, both It should be understood that they can be used alone or in combination.

Referring to FIGS. 6 and 7, another embodiment is shown. supersonic nozzle 1 has a shield material 22 disposed around a part of the outer surface 15 of the nozzle body 2. do.

The shield material is formed of two parts 22a and 22b, and is attached to a large number of bolts 23. These bolts also connect the upper part 3 of the nozzle body 2 and It holds the lower part 4 together. The shield material 22 extends beyond the outlet 9 in the flow direction. shown to be released. An exit opening 24 is formed in the end 25 of the shielding material 22. It is. The outlet opening 24 is defined by a perimeter 26, as shown in FIG. The whole is aligned with the outlet 9. The outlet opening 24 is larger than the outlet 9 and As shown, it is preferably at least 25% larger than outlet 9.

FIG. 8 shows a side view of shield portion 22b. See also Figures 9 and 10 Then, the shield material 22b has side portions 27a and 27b extending perpendicularly from the wall portion 28. has. As shown, reliefs 29 are formed in the wall portion 28 on each side. Step portions 30a and 30b are formed adjacent to portions 27a and 27b. Ru. At one end of the shield material 22b, between the side part 27a1 wall part 28 and the side part 27b An end portion 31 is formed at the end. A portion of the periphery 26 is formed by an end 31 .

Referring to FIG. 7, symmetrical shielding materials 22a and 22b meet outer surface 15. The nozzle body 2 is inserted through a spacer 33 arranged between the step portions 30a and 30b. , thereby reducing the space between the shielding material 22 and the nozzle body 2. All direct contact is prevented. The distance between the sides 27a and 27b is the outer surface 15 It is larger than the distance between a and 15e, and similarly the distance between the shield material 22 and the nozzle body 2 is Preventing direct contact between

Now, referring to FIG. 11, the supersonic nozzle 1 has a . The shield material 22 is partially shown in cross section. The exit cavity 34 of the supersonic passage 6 It is defined by the outlet 9, the shielding materials 22a, 22b and the outlet opening 24.

A cavity or gap 35 is formed between the shield material 22 and the outer surface 15. , which communicates with the surrounding environment with a cavity opening 36 at one end and an outlet cavity 3 at the other end. I am in contact with 4. The size of the gap 35 is determined by the size of the shield material due to the large number of spacers 33. By separating 22a and 22b from the outer surface 15, the shield material 22b is also This is further increased by the symmetrical relief of the relief 29 and the corresponding shield material 22a. Ru.

A seal is placed around the nozzle body 2 as shown in FIGS. 6, 11 and 12. Additional sound attenuation is achieved by assembling the material 22. nozzle body Sound transmission from the outer surface 15 of is reduced by the spacing of The sound reaching the shielding materials 22a and 22b is the shielding material. 22 is reflected and absorbed by the inner surface 37a of the shielding material. from the outer surface 37 of 22. Additionally, the outlet cavity 34 has an outlet opening 24. acts to reduce the shock waves that appear with the flow from outlet 9 before exiting through .

It is important that the outlet opening 24 does not act as an outlet of the supersonic nozzle 1. this An auxiliary air flow passes through the air gap 35 to prevent ultrasonic It exits through the outlet opening 24 in combination with the fast flow. Auxiliary air through air gap 35 The air supply is limited to any part of the outlet cavity 34 for the actual supersonic flow at the outlet 9. It must be sufficient to prevent the effect. In fact, the shielding materials 22a and 22 By maintaining the depth of the relief 29 formed in b at 0.050 inch, the Supplemental air flow was achieved.

The auxiliary air flow mixes with the supersonic air flow while exiting through the outlet opening 24. turbulence and other undesirable effects, mixing of the two streams is possible. It is best for this to occur tangentially. For this purpose, the nozzle 1 is placed at an angle of less than 60 degrees. 38, but if the outer surface 15 of the end 39 of the nozzle body 2 Optimal results will be obtained if the angle 38 formed with the surrounding area 26 is 60 degrees or more. It was found that Angle 38 is called the gap angle.

It is expected that the nozzle body will be formed of aluminum. Shield material 22 is yellow May be formed of copper or other similar materials. Spacer 33 separates the spacer from outer surface 15. In order to reduce the transmission of sound to the shielding material 22 through the sensor 33, Formed from inferior fibrous materials. The shield material 22 has grooves 17 and 2.5 to 6.0 Recommended for use in conjunction with supersonic nozzles with exit/throat ratios in the range Although expected, the shielding material actually attenuates the sound regardless of the presence of the groove 17. Ru. Of course, for optimal sound attenuation, the preferred implementation requires these three features. Equipped with all the following. Furthermore, those skilled in the art will appreciate that the outer surface 37 of the shield material 22 has a concave surface. By further arranging the locations and inserts (not shown), the preferred embodiment It can be seen that the voice attenuation performance is improved.

FIG. 12 shows the end face of the nozzle in FIG. 6, with the shield material 22 partially cut away. There is. As can be seen, the outlet opening 24 is aligned with the outlet 9. The void 35 is It extends around the entire nozzle body between the outer surface 15 and the inner surface 37a of the shield material 22. ing.

The present inventors have discovered that 2.6 A nozzle according to the invention with an outlet/throat ratio of 9 is 112 d at the operator's location. It has been found that the sound pressure level of BA is produced. Add shielding material to this nozzle. further sound attenuation is achieved and the sound pressure level at the operator's position is It is reduced to as low as 104 dBA.

FIG. 13 shows another embodiment of the invention having an elongated nozzle body 40 with a seal As described above, the material 41 is located near the end of the nozzle body 40 in conjunction with the embodiment of FIG. It is fixed in many places.

Figure 14 shows a supersonic passage with a circular cross section in combination with a groove formed on the inner wall of the supersonic passage. 2 shows another embodiment having a passageway around the nozzle body and spaced therefrom. It is arranged as follows.

In summary, numerous benefits obtained by using the concepts of the present invention have been described. Ta. The supersonic nozzle described here has highly attenuated sound pressure levels at the operator's location. , which provides greater safety and its easier use.

The foregoing description of preferred embodiments of the invention has been presented for purposes of illustration and description. and is not intended to limit the invention to the precise material formed and disclosed. do not have.

Obvious modifications or variations are possible in light of the above teachings. The embodiment is based on this invention have been selected and described to best illustrate the principles of light and their practical application. Therefore, one skilled in the art can adapt the invention to suit the particular intended use. can be optimally utilized in various embodiments and various modifications. Main departure The scope of the invention should be considered as defined by the claims appended hereto. be.

I6 3 international search report

Claims (41)

[Claims] 1. (a) a nozzle body having an outer surface; and (b) an inlet formed in the nozzle body; a supersonic passageway having a mouth, a throat and an outlet and defined by an interior wall; , the supersonic passage also includes a convergence zone from the inlet to the throat and a convergence area from the inlet to the throat. It has an expanding area from the funnel to the outlet, and the sonic flow at the throat and a supersonic flow in the expanded area, Additionally, the passageway has an exit/throat ratio in the range of 2.5 to 6.0, thereby During operation of the nozzle, the static pressure of the supersonic flow at the outlet is lower than the ambient static pressure. A sound-attenuating supersonic nozzle connectable to a stream of compressible fluid, characterized in that: 2. further comprising a plurality of longitudinal grooves formed in the inner wall adjacent the outlet. , whereby during operation of the nozzle, the supersonic flow produced by the supersonic flow in the supersonic passageway is 2. The nozzle of claim 1, wherein the nozzle prevents the merging of different shock waves. 3. The longitudinal groove extends inwardly from the outlet toward the throat of the nozzle. during operation of the supersonic flow to a point within said expanded area where the static pressure of the supersonic flow is equal to the ambient static pressure. The nozzle according to claim 2. 4. 3. The depth of said groove is in the range of 0.005 to 0.015 inches. nozzle. 5. 3. The distance between said grooves is in the range of 0.030 to 0.050 inches. Included nozzle. 6. The supersonic passage has an elongated rectangular cross-sectional shape formed by two sets of opposing surfaces. 3. wherein the longitudinal groove is formed in a pair of opposing surfaces. nozzle. 7. (a) a nozzle inlet connected to the nozzle body; and (b) a nozzle inlet connected to the nozzle body. an inlet passageway formed therein, the inlet passageway configured to accommodate a flow of compressible fluid. and configured to receive a stream of compressible fluid and direct a flow of compressible fluid to the inlet of the supersonic passageway. The inlet passage has an inlet of circular cross section and an outlet of rectangular cross section. The nozzle according to claim 6. 8. 7. The nozzle inlet according to claim 6, wherein the nozzle inlet is configured for use in a rapid separation mechanism. Nozzle as described. 9. 2. The nozzle body according to claim 1, further comprising a plurality of recesses formed in the outer surface of the nozzle body. Included nozzle. 10. Furthermore, a large number of 10. The nozzle of claim 9 including an insert. 11. 11. The nozzle of claim 10, wherein the insert does not extend beyond the outer surface. . 12. The insert is made of a material different from the material of which the outer surface of the nozzle body is formed. The nozzle according to claim 10, wherein the nozzle is formed of. 13. The nozzle of claim 9, wherein the recess is formed longitudinally in the outer surface. Le. 14. Furthermore, a large number of 14. The nozzle of claim 13, including an insert. 15. 15. The nozzle of claim 14, wherein the insert does not extend beyond the outer surface. . 16. The insert is made of a material different from the material of which the outer surface of the nozzle body is formed. 15. The nozzle according to claim 14, wherein the nozzle is formed of: 17. the insert is larger than the material of which the outer surface of the nozzle body is formed; 17. The nozzle of claim 16, wherein the nozzle is formed of a dense material. 18. (a) a number of longitudinal grooves formed in said inner wall adjacent said outlet; Thus, during operation of the nozzle, the supersonic flow within the supersonic passageway (b) a plurality of longitudinal grooves to prevent convergence of shock waves generated by the (c) having a shape complementary to said recesses; and The nozzle of claim 1, further comprising a plurality of inserts disposed in the recess. 19. 19. The nozzle of claim 18, wherein the insert does not extend beyond the outer surface. . 20. The insert is made of a material different from the material of which the outer surface of the nozzle body is formed. 19. The nozzle according to claim 18, wherein the nozzle is formed of: 21. the insert is larger than the material of which the outer surface of the nozzle body is formed; 21. The nozzle of claim 20, wherein the nozzle is formed of a dense material. 22. The longitudinal groove extends inwardly from the outlet toward the throat. During operation of the spool, the static pressure of the supersonic flow extends to a point within said expanded area that is equal to the ambient static pressure. 19. The nozzle according to claim 18. 23. 19. The depth of the groove is in the range of 0.005 to 0.015 inches. Nozzle as described. 24. 18. The distance between the grooves is in the range of 0.030 to 0.050 inches. Nozzle described in. 25. The supersonic passage has an elongated rectangular cross section formed by two sets of opposing surfaces. 19. The structure of claim 18, wherein the longitudinal groove is formed in a pair of opposing surfaces. Nozzle as described. 26. (a) a nozzle inlet connected to the nozzle body; and (b) the nozzle inlet. an inlet passageway formed in the for receiving a stream of compressible fluid and directing a flow of compressible fluid to the inlet of the supersonic passageway. wherein the inlet passageway has an inlet of circular cross-section and an outlet of rectangular cross-section. A nozzle according to claim 25. 27. Claim 2, wherein the nozzle inlet is configured for use in a rapid separation mechanism. 5. The nozzle according to 5. 28. (a) a nozzle body having an outer surface; (b) formed on the nozzle body; a supersonic passageway having an inlet, a throat and an outlet and defined by an inner wall; In addition, the supersonic passage also includes a convergence area from the inlet to the throat and a convergence area from the inlet to the throat. It has an enlarged area from the throat to the outlet, and the sonic flow at the throat and is configured to cause a supersonic flow in the expansion zone; Further, the passageway has an exit/throat ratio in the range of 2.5 to 6.0, thereby When the nozzle is in operation, the static pressure of the supersonic flow at the outlet is lower than the ambient static pressure. ,moreover (c) disposed about the outer surface of said nozzle body and in the flow direction beyond said outlet; and (d) a supersonic transmission line formed by the shielding material and (d) extending from the shielding material. is aligned with the outlet of said outlet, has a complementary shape to said outlet, and has a cross-sectional area smaller than said outlet. an outlet opening having a cross-sectional area of at least the same size; (e) The exit of the supersonic passage, the shield material, and the exit opening of the shield material. an outlet cavity defined by sound-attenuating supersonic nozzle. 29. Claim: the exit opening is at least 25% larger than the exit of the supersonic passageway. The nozzle according to item 28. 30. further comprising a first means for flowing auxiliary air into the outlet cavity; A first means for directing said supplemental air flow through an outlet opening in said shielding material. 29. A nozzle as claimed in claim 28, including means for. 31. the first means includes a gap formed between the outer surface and the shielding material; The cavity communicates with the surrounding environment at one end and with the outlet cavity at the other end. 31. A nozzle as claimed in claim 30, in communication. 32. the outlet opening has a periphery, and further formed between the outer surface and the periphery; 32. The nozzle of claim 31, comprising a gap angle of at least 60 degrees. 33. Claim 2: The shielding material does not directly contact any part of the outer surface. 8. The nozzle according to 8. 34. A spacer is disposed between the shield material and the outer surface of the nozzle body. 34. The nozzle according to claim 33. 35. further comprising a plurality of longitudinal grooves formed in the inner wall adjacent the outlet. and thereby, during operation of said nozzle, by the supersonic flow in said supersonic passage. 29. A nozzle according to claim 28, which prevents merging of generated shock waves. 36. The longitudinal groove extends inwardly from the outlet toward the throat. During operation of the spool, the static pressure of the supersonic flow extends to a point within said expanded area that is equal to the ambient static pressure. 36. The nozzle according to claim 35. 37. 36. The depth of said groove is in the range of 0.005 to 0.015 inches. Nozzle as described. 38. 35. The distance between the grooves is in the range of 0.030 to 0.050 inches. Nozzle described in. 39. The supersonic passage has an elongated rectangular cross section formed by two sets of opposing surfaces. 36. The structure of claim 35, wherein the longitudinal groove is formed in a pair of opposing surfaces. Nozzle as described. 40. (a) a nozzle inlet connected to the nozzle body; and (b) the nozzle inlet. an inlet passageway formed in the for receiving a stream of compressible fluid and directing a flow of compressible fluid to the inlet of the supersonic passageway. wherein the inlet passageway has an inlet of circular cross-section and an outlet of rectangular cross-section. 39. A nozzle according to claim 38. 41. Claim 3, wherein the nozzle inlet is configured for use in a rapid separation mechanism. 8. The nozzle according to 8.