EP0291892A2 - Flexibler Hohlreflektor - Google Patents

Flexibler Hohlreflektor Download PDF

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Publication number
EP0291892A2
EP0291892A2 EP88107777A EP88107777A EP0291892A2 EP 0291892 A2 EP0291892 A2 EP 0291892A2 EP 88107777 A EP88107777 A EP 88107777A EP 88107777 A EP88107777 A EP 88107777A EP 0291892 A2 EP0291892 A2 EP 0291892A2
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EP
European Patent Office
Prior art keywords
box
structures
elements
plate
pair
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP88107777A
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English (en)
French (fr)
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EP0291892A3 (de
Inventor
Samuel Joseph Caprette
Lawrence John Howard
Bernie Fink
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Goodrich Corp
Original Assignee
BF Goodrich Corp
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Filing date
Publication date
Application filed by BF Goodrich Corp filed Critical BF Goodrich Corp
Publication of EP0291892A2 publication Critical patent/EP0291892A2/de
Publication of EP0291892A3 publication Critical patent/EP0291892A3/de
Withdrawn legal-status Critical Current

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    • G—PHYSICS
    • G10—MUSICAL INSTRUMENTS; ACOUSTICS
    • G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
    • G10K11/00—Methods or devices for transmitting, conducting or directing sound in general; Methods or devices for protecting against, or for damping, noise or other acoustic waves in general
    • G10K11/18—Methods or devices for transmitting, conducting or directing sound
    • G10K11/20—Reflecting arrangements
    • G10K11/205—Reflecting arrangements for underwater use

Definitions

  • This invention relates to sonic reflectors or barriers configured for use in a marine environment, more particularly to sonic reflectors adapted for use in a marine environment at depths characterizing the operation of deep water submersibles, and most particularly those sonic reflectors configured for operation in a deep water environment in connection with sonic arrays.
  • Sonic reflectors are known in the art. Historically sonic reflectors have been divided into generally two basic categories: one group being so-called low-pressure reflectors finding utility in marine environments of modest depth; the other group being configured for operation at greater depths.
  • baffles are often formed from rubber having air-­filled cells therein or, alternately, thick sheets of rubber covered metal.
  • sheets of rubber having airfilled cavities therein tend to lose effectiveness, at least in part because of elevated hydrostatic pressures encountered and in part due to long immersion. Thick rubber covered plates in such deep water environments may be difficult to tune and through sheer bulkiness can provoke operational difficulties particularly where it is desired that low frequencies be reflected.
  • Squashed-tube baffles are shown and described, for example, in U.S. Patent 3,021,504 (Toulis). Squashed-tubes are typically formed by compressing a metallic tube into a permanently deformed ovaloid configuration. Such deformed tubes may then be grouped in bundles oriented to have longitudinal axes thereof generally parallelly coplanar, or otherwise oriented to define a curvilinear surface formed of the generally parallelly oriented squashed-tubes.
  • squashed-tubes may be oriented in ranks, squashed-tubes within a particular rank being generally parallelly oriented, and the ranks may be applied to the surface of vessels such as submarines in order to shield sonic arrays mounted thereover from sonic interference emanating from within the vessel.
  • squashed-tubes may be encapsulated in rubber. Encapsulation can assist in assuring against water infiltration into the squashed-tube with consequent, attendant, disruption of reflecting or baffling capability. Depending upon the nature and construction of the rubber encapsulant, encapsulation can assist in enhancing reflection or baffling characteristics associated with a squashed-tube array.
  • squashed-tube baffle arrays to an external surface of a vessel, it may be desirable to utilize more than a single rank of such squashed-tubes with each rank being a series of squashed-tubes arranged to define a sheet-like formation in a plane generally parallel to an external surface of the vessel, squashed-tubes in each rank being of a different physical size.
  • This difference in physical size of the tubes forming each rank assists in baffling or reflecting different sonic frequencies.
  • Both the width of individual tubes between different arrays may vary, and the thickness of metal walls defining the tubes may vary from rank to rank to enhance a capability for the array handling a variety of sonic frequencies.
  • the squashed-tubes respond to increasing hydrostatic pressure as a submersible embodying an array of such squashed-tubes descend through the depths.
  • the tubes flatten even more at the greater marine depths, but typically maintain a pocket of air therein to continue a reflector or baffling function.
  • the squashed-tube may flatten to the extent that center portions of the long radius curvilinear surfaces of the ovaloid defined by the tube touch one to the other thereby mechanically supporting the squashed-tube in some measure against additional collapse.
  • squashed-tubes have been formed from a relatively spring-like or elastic material, that is one tending to return to a physical configuration characterizing the tube prior to hydrostatic compression, the squashed-tubes, with a rise of the submersible from great depths will resume their previously ovaloid configuration.
  • the Junger prediction is based upon a flat-plate model of an array having flat-plate surfaces associateed with tubular members of the array; arrays formed from squashed-tubes, in part because of their ovaloid configuration, do not approach the acoustic performance predicted by a flat plate model as accurately as, perhaps, are array formed from essentially flat plate structures may.
  • squashed-tubes may become to some extent permanently deformed from a naturally ovaloid configuration thereby permanently interfering with a capability for an array of the squashed-tubes to perform satisfactorily as a baffle or reflector.
  • baffles formed of an array of tubular structures having a flat plate general configuration could find utility in deep water applications.
  • baffles can be formed economically employing readily available materials, and are less susceptible to crush damage from inadvertent exposure to excessive hydrostatic pressures, the potential utility is even greater.
  • the present invention provides a sonic reflector configured for use in a marine environement.
  • the sonic reflector includes a plurality of hollowed box-like structures each formed of at least two discreet plate-like longitudinal, mechanical, parallelly oriented elements.
  • Each box-like structure is possessed of a length substantially in excess of the width or thickness thereof.
  • the box-like structures are arranged generally in at least one rank with box-like structures within particular ranks having lengths thereof oriented substantially parallelly.
  • the box-like structures thereby may define a planar-like rank or a curvilinear surface.
  • At least one elastomeric encapsulant surrounds and encapsulates the individual box-like structures.
  • the elastomeric encapsulant is formed principally of an elastomer imparting to the elastomeric encapsulant ply desired acoustic properties.
  • the longitudinal mechanical elements are or comprise a pair of plate-like elements configured in a generally parallel plane relationship and spaced one apart from the next to a desired extent.
  • Spacers are provided, unattachedly configured to support and separate the plate-like elements to the desired spaced-apart extent.
  • the spacers are configured in the form of T-blocks or curvilinear bearing surfaces with the curvilinear bearing surfaces typically being rods, rod segments, or balls.
  • the parallel plate-like elements include channels formed therein configured to receive the curvilinear bearing surfaces thereby reducing an opportunity for movement of the curvilinear bearing surfaces from a desired position configured to establish the spaced apart relationship between the plate-like elements.
  • the plate-like elements may be bent at edges thereof, one towards the next to form a box-like structure.
  • each box-like structure includes end closures unattachedly configured to function as end plates, closing the box-like structures and thereby supporting the elastomeric encapsulant where encapsulating the box-like structures adjacent end portions, the end portions being defined with respect to a longitudinal dimension of the box-like elements defining generally the plate-like ranks.
  • the reflector of the invention is preferably configured for mounting to an outer surface of the deep water submersible such as a submarine.
  • the reflector is further configured to reflect sonic frequencies emanating from within the submersible and, in preferred environments, thereby protect an acoustic array such as a sonar array positioned on a surface of the reflector obverse to that attached to the submersible from spurious acoustic frequencies emanating from within the submersible.
  • Figure 1 is a perspective embodiment of a reflector 10 made in accordance with the invention.
  • the reflector 10 includes a plurality of individual bos-like structures 12.
  • the box-like structures 12 are possessed of a length 13 substantially in excess of width 14 and height 15.
  • Straps 16 function to hold together bundles 17 of the box-like structures 12.
  • the bundles 17 each contain box-like structures 12 with the box-like structures 12 each being a part of a separate rank 18, 18′, 18 ⁇ of generally coplanar box-like structures having lengths 13 oriented substantially co-parallelly. From one rank 18, 18′, 18 ⁇ to the next, the width 14 and/or thickness 15 of individual box-like structures within the ranks may vary.
  • a backplate 19 is employed in Figure 1 to which the stacks 17 of box-like structures 12 are fixed.
  • the backplate 19 can be formed of any suitable or conventional material such as rubber, steel or the like and is affixed to an outer hull, shown generally at 20, of a vessel such as a submarine or other deep water submersible. Affixation of the backplate 19 to the hull 20 can be accomplished in appropriate, well-known manner such as by welding, riveting, attachment employing clips, and the like.
  • Figure 2 depicts one preferred embodiment of a box-like structure 12 suitable for use in the sonic reflector 10.
  • the box-like structures 12 includes a height 15 and a width 14.
  • a length dimension 13 is defined by a pair generally parallel plate-like elements 30, 32.
  • Edge portions 34, 36 of each plate-like element 30, 32 are deformed generally one towards the other by bending or the like to define an engagement zone 38 where the edge portions 34, 36 meet.
  • the engagement zone 38 represents an inter­section between the edges portions 34, 36.
  • the edge portions 34, 36 function to support the plate-like elements 32, 30 in a spaced apart relationship.
  • An end closure 40 functions to close ends of the box-like structure 12.
  • the end closure 40 is configured to be of a greater width at end portions 42 thereof in contrast to central portions 44 thereof. This difference in width functions to provide an accommodation for bending motion of the plate-like elements 30, 32 one towards the next primarily at center portions thereof while the box-like structure is subjected to hydrostatic pressures impinging thereon by reason of a reflector 10 embodying the box-like structure 12 being operated at significant depth in a marine environment.
  • the end closure 40 or so-called "dog bone” by reason of its particular width profile thereby functions to close effectively the end of the box-like structure 12.
  • a similar dog bone is positioned at a remaining end of the box-like structure (not shown in Figure 2).
  • a similarly shaped dog bone structure (not shown) formed of a plastic such as nylon between the dog bone 40 and the plates 30, 32 to assure against noise as the plates move relative to the dog bone 40.
  • An elastomeric encapsulant 48 surrounds the box-like structure 12.
  • the encapsulant 48 can be of any suitable or conventional nature but in one preferred embodiment includes at least one fabric ply formed of a fabric coated on one or both surfaces with a plasticizing or rubberizing compound and one or more elastomeric or rubber plies attached thereto.
  • the elastomeric encapsulant 48 will consist of one or more plies of a rubberized fabric such as nylon fabric grade 80 available from the B.F. Goodrich Company having vulcanizably bonded thereto on one surface a sheet ply of rubber and vulcanizably bonded thereto on an outer surface a sheet ply of a rubber containing therein a biologically active substance.
  • Nofoul® rubber available from the B.F. Goodrich Company can be employed as the biologically active substance containing ply.
  • the biological activity of the outer rubber ply functions to retard the accumulation of marine deposits such as barnacles and other dysfunctional marine growth upon the elastomeric encapsulant 48. Since following vulcanization or curing the plies forming the elastomeric encapsulant 48 become substantially inseparable, the individual plies are not depicted in the Figures. Making of elastomeric fabric reinforced materials suitable for use as encapsulants are well-known in the art.
  • the elastomeric encapsulant 48 encapsulate the box-like structure completely thereby preventing the movement of liquids such as seawater from points external to the box-like structure 12 to a central cavity 46 defined by the plate-like elements 30, 32 of the box-like structure 12 and the dog bones 40. It is this central cavity 46 that, in significant measure, provides desirable sonic reflection or sonic barrier characteristics to a plurality of the box-like structures 12 when arranged in an array or reflector 10 as shown in Figure 1.
  • the dog bone or variable width configuration of the end closures 40 depicted in Figure 2 functions to reduce tearing stresses and deformation imposed on the elastomeric encapsulant 48 as the plate-like elements 30, 32 deform one towards the next by bending when subjected to hydrostatic pressure.
  • the end closure 40 typically is not affixed to the plate-like elements 30, 32.
  • the unattached end closure 40 can thereby readily accommodate positional changes necessary to react to bending or shifting movement of the plate-like elements 30, 32 in response to hydraulic loadings imposed thereon and changes in overall dimensional configuration of the box-like elements 12 associated with changes in temperature and other environmental factors impacting upon the box-like elements 12 forming a reflector 10.
  • the box-like element 12 as depicted in Figure 2 differs from more conventional squashed -tube configurations, in that the plate-like elements 30, 32 present a nearly parallel plane interface with the marine environment in which the reflector 10 is operated, thereby facilitating a calculation of the proper configuration and sizing of the elements 30, 32, 48, 46 of the box-like elements 12 to intercept particular, desired sonic frequencies.
  • the end closure 40 provides a desirable alternate to a traditional pinch-type closure characterizing or typifying squashed-tubes employed for reflectors.
  • the end closure of Applicant's invention provides for a reduced zone of stress on the elastomeric encapsulant 48 at end portions of the box-like structures 12 made in accordance with the invention.
  • FIG. 3 an alternate preferred embodiment of the box-like structure 12 is depicted wherein a pair of generally parallel, plate-like elements 50, 52 are separated by T-blocks 54, 56.
  • the T-blocks include a spacer portion 58 and ears 59.
  • the ears 59 function to suppress a tendency for the plate-like elements 50, 52 to shift laterally in parallel planes one with respect to the other while the spacer portions 58, unattached to the plates, function to separate the plate-like elements 50, 52 to a desired extent establishing the parallel planar relationship therebetween.
  • the separation of the plates 50, 52 and thereby impart the volume parameters of the cavity 46 can be determined in substantial part by the selection of the dimensions of the spacer portion 58 of the T-blocks 54, 56, subject of course to deformation effects attributable to the effects of hydrostatic pressure upon the plate-like elements 50, 52.
  • the cavity 46 associated with the box-like structure 12 as depicted in Figure 3 can thereby be defined as a function of a width dimension of the plate-like elements 50, 52, a longitudinal dimension of the plate-like elements 50, 52 and the spacing between the plate-like elements defined by the spacer block 58.
  • This cavity 46 is possessed of a volume that changes with distortional bending of the plate-like elements 50, 52 under hydrostatic forces.
  • the plate-like elements 50, 52 of the box-like structure as depicted in Figure 3 define a more ideal parallel plate configuration facilitating modeling of some performance of an array of the structures 12 employing more simplistic calculation of the sonic frequency reflecting/barring capabilities for a particular embodiment of a box-like structure 12 made in accordance with Figure 3.
  • an elastomeric encapsulant surrounds the T-blocks 54, 56 and the plate-like elements 50, 52.
  • a pair of end closures can be employed in the manner depicted in Figure 2 to close the ends of the box-like structure 12 as depicted in Figure 3.
  • Any such end closures 40 preferably embody a "dog bone" configuration facilitating accommodation of bending movement engendered in the plate-like elements 50, 52 by dint of hydrostatic pressure encountered by operation of the box-like structures 12 between marine environments of varying depths.
  • Any elastomeric encapsulant employed in box-like structures 12 as depicted at Figure 3 is subject to the same selection criteria as would apply to the elastomeric encapsulant for box-like structures 12 depicted in Figure 2.
  • FIG 4 a still further preferred embodiment of the invention is shown wherein a pair of plate-like elements 60, 62 are positioned in a generlly parallel relationship.
  • the plate-like elements 60, 62 are separated by a pair of rod elements 64, 66.
  • Each rod element 64, 66 presents a generally curvilinear bearing surface to the plate-like elements 60, 62 as would be inherent in a rod-like structure having a curvilinear exterior surface.
  • rod-like elements 64, 66 could equally be rods having a rectilinear cross-section such as quadrangles, hexangles, or octangles, without limitation, and such rectilinear cross-sections for purposes of this specification shall be deemed also to present a bearing surface which, for purposes of the embodiment depicted in Figure 4, and shall therefor be deemed to be "curvilinear".
  • Channels 67 are formed in the plate-like elements 60, 62 with the channels 67 being configured to receive curvilinear bearing surfaces associated with the rods 64, 66.
  • An elastomeric encapsulant 68 including a fabric reinforced subply 69 therein encapsulates the box-like structure 12 of Figure 4 in a manner similar to the function of the elastomeric encapsulant 48 in Figure 2.
  • the channel 67 function to assist the elastomeric encapsulant 68 in retarding lateral shifting of the plate-like elements 60, 62 within the plane occupied by each, under the stresses and strains of operation in deep water marine environment.
  • end closures (not shown in Figure 4 for clarity) similar to the end closures 40 shown and depicted in Figure 2 may be employed to close the ends of the box-like structures 12 of Figure 4.
  • Any such end closures preferably are of a "dog bone" configuration that is wider at ends thereof than towards the center thereof to accommodate more readily distortional bending of the plate-like elements 60, 62 under the duress imposed by hydrostatic forces encountered by operation of the box-like structures 12 of Figure 4 at varying depths in a marine environment.
  • the rods 64, 66 need not be continuous for a full length of the plate-like elements 60, 62.
  • the rods 64, 66 may instead be rod segments presenting the necessary curvilinear bearing surface and positioned as required generally end-to-head to establish support for the plate-like elements 60, 62 along a length of the channels 67.
  • the rods 64, 66 may instead be balls presenting a curvilinear support surface.
  • the channels 67 may include sufficient of any such balls to provide an effectively continuous support for the plate-like members 60, 62.
  • box-like structures 12 of the invention present a virtually uniform flat-plate configuration facilitating more simplistic prediction of the baffling or reflecting performance of arrays 10 of the box-like structures 12 to impinging sonic frequencies
  • the elastomeric encapsulants 48, 68 as depicted in Figures 2 and 4 typically include a core ply designated at reference numeral 69 in Figure 4 formed from a fabric reinforced elastomer or so-called coated fabric.
  • fabric what is meant is knit, woven, cord, wire, cable or chopped fiber reinforcement formed from suitable or conventional natural or synthetic fibrils such as steel, polyester, polyaramide, polyimide and the like resistant to the effects of and acceptable for use in a marine environment. These fibrils may, optionally, have been spun and/or otherwise formed into bundles of fibrils for purposes of providing reinforcing cords, mesh, knit, or other fabric materials. If chopped, the chopped fiber can either be chopped monofilaments or fibrils or may be a chopped fiber derived from chopping spun or otherwise bundled fibrils.
  • the elastomers used in forming the core ply 69 can be of any suitable or conventional nature and may include natural rubber, synthetic rubbers such as chlorinated (NEOPRENE® available from duPont), silicone, and similar rubbers, or may be polybutadiene, acrylonitrile, butadiene co-polymer, or styrene-butadiene rubbers.
  • natural rubber synthetic rubbers such as chlorinated (NEOPRENE® available from duPont), silicone, and similar rubbers, or may be polybutadiene, acrylonitrile, butadiene co-polymer, or styrene-butadiene rubbers.
  • coated fabric and elastomer employed in fabricating the core ply 69 will be at least in part a function of the destructive forces to which the elastomeric encapsulant 68 will be subjected in the marine environment, the temperature and acoustic conditions under which the elastomeric encapsulant 48, 68 is to be employed, and the degree of elasticity and acoustic hydrodynamic properties it is desired the elastomeric encapsulant 48, 68 demonstrate upon exposure to hydrostatic forces applied thereto.
  • coated fabric such as fabric reinforced rubberized sheeting is well-known and conventional well-known techniques may be employed for fabricating the elastomeric encapsulant 48, 68.
  • the elastomeric encapsulant 48, 68 can be formed from castable liquid polymers.
  • the formation of structures from castable liquid polymers is known in the art. Criteria controlling the selection of a particular castable elastomer will be similar to those governing the selection of other elastomers as set forth herein. Examples of suitable castable liquid polymers would include polyurethanes, Hycar® reactive liquid polymers (BFGoodrich) and silicones.
  • the elastomeric encapsulant 48, 68 may include a filling agent in any rubber or other elastomeric compounding materials.
  • This filling agent which may be present in a quantity of between 0 and about 80 parts per hundred weight of the rubber or other elastomer forming the elastomeric encapsulant 48, 68 and, generally is present in a quantity of between 0 and 40 parts per hundred weight of the rubber or other elastomer forming the elastomeric encapsulant 48, 68 and may be a particulate such as carbon black, glass microspheres, or microbeads, or may be a fiber-like additive (in addition to any used in a core ply 69 as shown in Figure 4) such as mineral, polyester, polyolefin, polyaramide, polyamides, polyimides, polyvinyls, such as polyvinyl alcohol (e.g.
  • the extend to which fillers are employed in fabricating the elastomeric encapsulant 48, 68 is at least in part a function of the dynamic, acoustic hydrodynamic properties such as longitudinal propagation, attenuation and loss tangent characteristics desired for those acoustic wave forms anticipated as impacting the reflector 10 and by any dynamic modulus, static modulus and Young modulus properties it is desired be achieved in any resulting elastomeric encapsulant 48, 68.
  • "Elastomeric” or “elastomer” as used in connection with this invention shall mean a material possessed of an ability to recover, at least in significant part, a former shape or configuration upon removal of a configuration or shape distorting force.
  • rubber as used in connection with this invention what is meant is a vulcanized, or otherwise cross-linked elastomer made according to conventional, well-known techniques.
  • the elastomeric encapsulant 48, 68 be possessed of: a static tensile modulus of between about 200 psi (1380 kPa) to about 2000 (13,800 kPa) psi; a Youngs modulus of between about 200 psi (1380 kPa) and about 2000 psi (13,800 kPa); a density of between about 1.0 and about 1.5 grams/cc 3; loss tangent properties of between about 0.05 and about 0.40 (units); dynamic shear modulus (dynes/cm2) properties of 107; and a static shear modulus property of between about 65 psi (442 kPa), and about 700 psi (4825 kPa).
  • Youngs modulus what is meant is a ratio of the simple tension stress applied to a material to the resulting strain parallel to the tension.
  • the Younds modulus is also a measure of the modulus elasticity for the material, which modulus of elasticity may also be known as a co-efficient of elasticity, the elasticity modulus, or the elastic modulus.
  • tensile modulus what is meant is a tangent or secant modulus of elasticity of a material in tension.
  • density what is meant is weight/unit volume.
  • loss tangent waht is meant is a ratio of the viscous modulus to the elastic modulus for a particular material.
  • viscous modulus what is meant is that modulus proportional to a deforming force not recovered or conserved.
  • the viscous modulus typically is observed only under dynamic stress.
  • elastic modulus what is meant is a ratio of an increment of some specified form of resulting stress to the increment of some specified form of strain which may also be known as the co-efficient of elasticity.
  • the elastic and viscous modulus are also herein referred to as dynamic modulus or moduli.
  • one source of noise in the operation of reflectors 10 comprising box-like structures 12 is what is known as stick/slip noise engendered at metal-to-metal contact surfaces between, for example, the curvilinear bearing surfaces of rods 64, 66 and the plate-like elements 60, 62.
  • the particularly curvilinear bearing surfaces of rods or balls as employed in the preferred embodiment depicted in Figure 4 tends to establish point or point-like contact between the plate 60, 62 and the rods 64, 66 which, it is believed, substantially reduces acoustic noise generated by stick/slip at the metal contact surfaces as the plates 60, 62 conform to changing hydrostatic conditions.
  • point contact develops with respect to the spacer portion 58 thereby establishing a limited zone for stick/slip acoustic noise generation.
  • Figures 2, 3 and 4 offer a substantial opportunity for improved stick/slip performance with respect to configurations such as are shown in the purely theoretical depiction of Junger, J. Accoust. Soc. Am.78(3), 9/65 pp 1010 .
  • One possible explanation is that these embodiments more closely resemble a simply supported beam in contrast to clamped beams of Junger. This simply supported beam construction appears to result in a lower inherent resonant frequency.
  • a ratio of ⁇ n for the simply supported beams of the invention to ⁇ n for the clamped beams of Junger at the lowest frequency approaches 0.50; ⁇ n being calculated from the operation where 1 is the beam length, ⁇ its mass/unit length, EI the bending stiffness, and a n a numerical co-efficient associated with particular boundary conditions for the beam at a specific frequency.
  • the plate-like elements 30, 32, 50, 52, 60, 62 can be made of any suitable or conventional material, but typically are made from a metal such as steel or stainless steel; substantial resistance to bending forces imposed by hydrostatic pressure is desirable in these plate-like element together with a freedom from metal fatigue tendencies that would be deleterious to performance of the box-like structure 12 under the frequent flexing of the plate-like elements 30, 32, 50, 52, 60, 62 engendered by in hydrostatic pressure changes as a result of operation of a submarine or the like embodying a box-like structure 12 in accordance with the invention at varying depths in a marine environment.
  • the plate-like elements 30, 32, 50, 52, 60, 62 can also be made of plastic or reinforced plastic materials such as fiberglass reinforced phenolics or epoxys and polyester reinforced epoxys or phenolics.
  • the materials forming the plate-like elements 30, 32, 50, 52, 60, 62 must withstand bending forces and be possessed of a substantial capability for recovery from bending engendered by hydrostatic forces encountered in service.
  • the selection of a particular material of construction for the plate-like elements 30, 32, 50, 52, 60, 62 will be a matter of some experimentation to optimize both structural and acoustic properties of the box-like structure 12.
  • the T-bars 54, 56 and the rods 64, 66 presenting curvilinear bearing surfaces can be formed of any suitable or conventional materials such as steel or stainless steel but, for weight considerations may also be formed of lightweight metals and metal alloys such as titanium, aluminum or other suitable or conventional, metal alloy materials.
  • the T-bars 54, 56 and rods 64, 66 can also be formed of plastic materials in accordance with the material criteria set forth for the plate-like elements 30, 32, 50, 52, 60, 52 or such other plastic materials or reinforced plastic materials as are capable of accepting the crushing forces associated with loadings imposed by the plate-like elements by reason of hydrostatic loading thereupon.
  • the rods 64, 66 typically are formed simply of hardened steel drill rod as such drill rod is readily commercially available in precision diameters.
EP88107777A 1987-05-20 1988-05-14 Flexibler Hohlreflektor Withdrawn EP0291892A3 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US5179987A 1987-05-20 1987-05-20
US51799 1987-05-20

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EP0291892A2 true EP0291892A2 (de) 1988-11-23
EP0291892A3 EP0291892A3 (de) 1989-09-27

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JP (1) JP2823864B2 (de)
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0328931A2 (de) * 1988-02-18 1989-08-23 The B.F. Goodrich Company Schallwand mit federnden Röhren
FR2730335A1 (fr) * 1995-02-02 1996-08-09 France Etat Dispositif anti bruit notamment pour accoustique sous-marine
US8910743B2 (en) 2010-07-16 2014-12-16 Subsea Asset Location Technologies Limited Acoustic Reflectors
FR3037705A1 (fr) * 2015-06-17 2016-12-23 Dcns Barriere acoustique de reduction des nuisances sonores sous-marines pour l'environnement

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2906993A (en) * 1946-05-22 1959-09-29 Raymond L Steinberger Transducer for underwater sound
US3021504A (en) * 1956-07-02 1962-02-13 William J Toulis Apparatus for controlling the effective compressibility of a liquid
FR2536195A1 (fr) * 1982-11-17 1984-05-18 Sintra Alcatel Sa Reflecteur acoustique sous-marin

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2906993A (en) * 1946-05-22 1959-09-29 Raymond L Steinberger Transducer for underwater sound
US3021504A (en) * 1956-07-02 1962-02-13 William J Toulis Apparatus for controlling the effective compressibility of a liquid
FR2536195A1 (fr) * 1982-11-17 1984-05-18 Sintra Alcatel Sa Reflecteur acoustique sous-marin

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA, vol. 78, no. 3, September 1985, pages 1010-1012, Acoustical Society of America, New York, US; M.C. JUNGER: "Water-borne sound insertion loss of a planar compliant-tube array" *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0328931A2 (de) * 1988-02-18 1989-08-23 The B.F. Goodrich Company Schallwand mit federnden Röhren
EP0328931A3 (de) * 1988-02-18 1991-07-31 The B.F. Goodrich Company Schallwand mit federnden Röhren
FR2730335A1 (fr) * 1995-02-02 1996-08-09 France Etat Dispositif anti bruit notamment pour accoustique sous-marine
US8910743B2 (en) 2010-07-16 2014-12-16 Subsea Asset Location Technologies Limited Acoustic Reflectors
FR3037705A1 (fr) * 2015-06-17 2016-12-23 Dcns Barriere acoustique de reduction des nuisances sonores sous-marines pour l'environnement

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Publication number Publication date
EP0291892A3 (de) 1989-09-27
JP2823864B2 (ja) 1998-11-11
CA1330954C (en) 1994-07-26
JPH01138592A (ja) 1989-05-31

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