Controlling Machinery Induced Underwater · PDF fileControlling Machinery Induced Underwater...

Controlling Machinery Induced Controlling Machinery Induced Underwater NoiseUnderwater Noise

Raymond Fischer, Noise Control Engineering, Inc.

NOAA Vessel Quieting Technology

NCE/NOAA SymposiumNCE/NOAA Symposium

ApproachApproach

How much U/W noise reduction is How much U/W noise reduction is required?required?Critical sourcesCritical sources–– MachineryMachinery–– Propulsor (covered by others)Propulsor (covered by others)Critical pathsCritical paths–– Airborne and structureborneAirborne and structureborneNoise/Vibration control approachesNoise/Vibration control approachesUse NOAA Fisheries R/V as illustrationUse NOAA Fisheries R/V as illustration


Range to achieve 120 dB LevelRange to achieve 120 dB Level

320021.51.8185Ship 21602.90.4172Ship 1

DREDGING

320021.51.8185Conical Drilling

Unit

3204.60.6175Drill Ship

Drill ship, rigs, platforms

1000046.43190Large Tanker126011.71181Supply Ship 1252.50.35171Tug & Barge

40.250.061565-m Zodiac

range, km Cylindricalspreading

range, km1.5 powerspreading

range, km Sphericalspreading

Source Level, dB re 1μPa

@1m

Ocean AttenuationOcean AttenuationAttenuation at 10 km

(Spherical spreading = 80 db)

0

10

20

30

40

50

60

70

80

90

100

10 20 40 80 160 315 630 1250 2500 5000 10000 20000 40000

Freq, Hz

Atte

n, d

B


Cargo Ship Broad Band NoiseCargo Ship Broad Band Noise

Radiated Noise Characteristics of a Modern Cargo Ship, Arverson & Vendittis, JASA 107 (1), Jan. 2000.

173 m Direct Drive

R adiated N o ise - A laska C ruise Ships

120

130

140

150

160

170

180

190

20 40 80 160 315 630 1250 2500 5000 10000 20000TOB Freq ( Hz)

Radiated Noise Radiated Noise –– Cruise ShipCruise Ship

Propeller Noise SourcesCavitation noise& structural re-radiation

Machinery Noise SourcesMain propulsion system

Structural-borne path

Sea-connected system

Ship Noise Sources

Aux. Equipment

Air-borne path


Various Drive Vibration LevelsVarious Drive Vibration Levels


Best Acoustic DesignBest Acoustic Design

Use inherently quiet equipmentUse inherently quiet equipment–– Rotating rather than reciprocatingRotating rather than reciprocatingUse (dynamically) stiff foundationsUse (dynamically) stiff foundationsPlace noisier equipment toward centerlinePlace noisier equipment toward centerlineUse double hulls or tanks outboard of Use double hulls or tanks outboard of Engine RoomEngine RoomDieselDiesel--Electric offers greatest opportunityElectric offers greatest opportunity–– Isolation mounts for Isolation mounts for gensetsgensets, quiet motors, quiet motors


Vibration IsolatorsVibration IsolatorsBest shipboard Best shipboard noise control noise control element.element.Reduces SB path.Reduces SB path.Isolation of Isolation of Propulsion Engines Propulsion Engines requires flexible requires flexible coupling and other coupling and other components.components.Use only Use only Elastomeric MarineElastomeric Marine--Grade Mounts.Grade Mounts.Requires Requires dynamically stiff dynamically stiff foundations.foundations.

Does not eliminate low frequency noise!


Two-stage Genset Isolation System for NOAA FRV

Upper Stage Mounts

Lower Stage Mounts


Acoustic InsulationAcoustic InsulationReduces AB & SSB Reduces AB & SSB Transmission.Transmission.Typically insulationTypically insulation’’s s base material is either base material is either fiberglass or mineral fiberglass or mineral wool.wool.High Transmission Loss High Transmission Loss (or HTL) material has (or HTL) material has middle layer of limp mass middle layer of limp mass (usually leaded vinyl).(usually leaded vinyl).Transmission Loss or Transmission Loss or STC (Sound STC (Sound Transmission Class) Transmission Class) defines performance.defines performance.


Treatment EffectivenessTreatment Effectiveness

005500Raft mount equipmentRaft mount equipmentSteel framingSteel framing

101010101010Bow Thruster TreatmentsBow Thruster Treatments55--101055--101000Damping; 2Damping; 2--3 3 psfpsf; $8; $8--$12/ft$12/ft22

55--10100055--1010Acoustic InsulationAcoustic Insulation3 to 8 3 to 8 pcfpcf; $1; $1--$4/ft$4/ft22

001010--2020

00Vibration Isolation Vibration Isolation –– passivepassive$20$20--$400/mt $400/mt

SSBSSBFSBFSBABABTreatmentTreatment

Values are approximate dB reduction of overall sound.

“Quiet Vessel” approximately 7% to 10% total cost of vessel. Quiet R/V 15% to 20% cost of vessel.


Follow ThroughFollow Through

All the treatments in the world will not overcome a poor inspection/QA and verification program!


Advanced TreatmentsAdvanced Treatments

Air layer (belt forward of engine room)Air layer (belt forward of engine room)–– Effective midEffective mid-- to highto high--frequency (10+ dB)frequency (10+ dB)–– Amplifies low freq (Amplifies low freq (--5 dB over 50 Hz bw)5 dB over 50 Hz bw)–– Holes can clog if not maintainedHoles can clog if not maintainedHull coatingHull coating–– Effectiveness depends on material Effectiveness depends on material

‘‘compliancecompliance’’ and thickness (>10 dB)and thickness (>10 dB)–– Adherence and damage issuesAdherence and damage issues


Advanced TreatmentsAdvanced Treatments

Active mount systemActive mount system–– Improved low frequency performanceImproved low frequency performance–– Cancels tones and multiplesCancels tones and multiplesKeep machinery inside hull (Keep machinery inside hull (AzipodsAzipodscurrently radiate significant mechanical currently radiate significant mechanical noise)noise)


Designer NOISEDesigner NOISEProgram for Program for shipboard noise shipboard noise predictionpredictionCreated under US Created under US NAVY SBIR ProjectNAVY SBIR ProjectPart of Flagship Part of Flagship Designer suite from Designer suite from Proteus EngineeringProteus EngineeringShip specificShip specific–– Modeling, constants, Modeling, constants,

etc.etc.


FRV-40 Noise Control Treatments

.

Specially designed by U.S. Navy (NSWC)Specially designed by U.S. Navy (NSWC)Hull & Hull & PropellerPropeller

Applied to hull and bulkheads (16 tons)Applied to hull and bulkheads (16 tons)Damping TilesDamping Tiles

Perimeter of Engine Room and other noisy Perimeter of Engine Room and other noisy spacesspaces

Acoustic Acoustic InsulationInsulation

Auxiliary Equipment & HVACAuxiliary Equipment & HVACSingle Stage Single Stage IsolationIsolation

Diesel Gens & Reciprocating EquipmentDiesel Gens & Reciprocating Equipment3512 system 3512 system –– 18,113 kg; 3508 system 18,113 kg; 3508 system ––14,770 kg14,770 kg

Double Stage Double Stage Vibration Vibration IsolationIsolation

Propulsion Motor Specially DesignedPropulsion Motor Specially DesignedLow Noise Low Noise EquipmentEquipment


FRV Radiated Noise FRV Radiated Noise –– 11 kts11 kts

Prediction ToolsPrediction ToolsDIFFERENCE BETWEEN MEASURED AND PREDICTED RADIATED NOISE - AOE-6

-6

-4

-2

0

2

4

6

8

10

31.5 63 125 250 500 1000 2000 4000 8000

OB FREQ (Hz)

DEL

TA, d

B

754.5’ LOA, 48,800 tons, twin screw


Range to 120 dB LevelRange to 120 dB Level

1.1.03150FRV-40

3200->3222->11.8->.02185-20=165Ship 2160->1.63->.10.4->.04172-20=152Ship 1

DREDGING3200->3222->11.8->.02185-20=165

Conical Drilling Unit

320->3.24.6->.20.6->.06175-20=155Drill Ship

Drill ship, rigs, platforms

10000->10046->2.13.2->.32190-20=170Large Tanker1260->12.612->.541.1->.11181-20=161Supply Ship

1302.50.4171Tug & Barge @

40.250.061565-m Zodiac

range, km Cylindricalspreading

range, km1.5 powerspreading

range, km Sphericalspreading

Source Level, dB re 1 μPa

@1m


SummarySummaryTechnology exists to evaluate and control ship Technology exists to evaluate and control ship noise & should be applied to vessels that noise & should be applied to vessels that operate in environmentally sensitive areasoperate in environmentally sensitive areasPrimary noise sources are the propulsion drives Primary noise sources are the propulsion drives –– low frequencies and the low frequencies and the propulsorspropulsors –– mid to mid to high frequency (can trump once high frequency (can trump once cavitatingcavitating))Drives should be selected based on having low Drives should be selected based on having low vibration source levels and/or utilizing vibration vibration source levels and/or utilizing vibration isolation mountsisolation mountsNovel treatments show potential but need Novel treatments show potential but need developmentdevelopment


ReferencesReferencesOn active vibration isolation of floating raft system, J. On active vibration isolation of floating raft system, J. NiuNiu, K. Song, & C. Lim, J. of Sound and , K. Song, & C. Lim, J. of Sound and Vibration, 285, 2005.Vibration, 285, 2005.Active Vibration Isolation in Ships, M. Active Vibration Isolation in Ships, M. WinberWinber, S Johansson, L , S Johansson, L HakanssonHakansson & I. & I. ClaessonClaesson, Intl. J of , Intl. J of Ac. & Ac. & VibVib., 10 (4), 2005.., 10 (4), 2005.Active Control of Engine Induced Noise in a Naval Application, MActive Control of Engine Induced Noise in a Naval Application, M WinbergWinberg, S Johansson, T Lag, , S Johansson, T Lag, 88thth Intl Congress on Sound & Intl Congress on Sound & VibVib, Hong Kong, 2001., Hong Kong, 2001.Optimization of Vibration Isolation Mounts for Application to ShOptimization of Vibration Isolation Mounts for Application to Shipboard Diesel Engines, A ipboard Diesel Engines, A MuravyovMuravyov & S Hutton, Nat. & S Hutton, Nat. DefenceDefence R&D Branch, DREA CR/97/437, April 1997.R&D Branch, DREA CR/97/437, April 1997.Effect of DragEffect of Drag--Reducing Air Lubrication on Underwater Noise Radiation from ShipReducing Air Lubrication on Underwater Noise Radiation from Ship Hulls, K. Hulls, K. MatveevMatveev, Trans. of the ASME, 137, Aug. 2005., Trans. of the ASME, 137, Aug. 2005.Simplified Structural Acoustic Characterization of External CompSimplified Structural Acoustic Characterization of External Compliant Coatings on Submerged liant Coatings on Submerged Surfaces, B. Sandman & J. Surfaces, B. Sandman & J. BoisvertBoisvert, NUWC Div. Newport Tech Digest, June 1995., NUWC Div. Newport Tech Digest, June 1995.Computational Evaluation of Damping and Decoupling Materials, PhComputational Evaluation of Damping and Decoupling Materials, Ph III, O. III, O. FoinFoin & A. Berry, Nat. & A. Berry, Nat. DefenceDefence R&D Branch, DREA CR/2000R&D Branch, DREA CR/2000--016, Feb 2000.016, Feb 2000.Introducing Decoupling Coatings in SEA Models, C. Introducing Decoupling Coatings in SEA Models, C. AudolyAudoly, Noise, Noise--Con 97, Penn State U., June, Con 97, Penn State U., June, 1997.1997.


NCE ReferencesNCE References““Airborne Noise Flanking of Shipboard Vibration Isolation SystemsAirborne Noise Flanking of Shipboard Vibration Isolation Systems,,”” Sound and Vibration, Dec. 2006.Sound and Vibration, Dec. 2006.““Underwater Radiated Noise of the NOAA Vessel OSCAR DYSON,Underwater Radiated Noise of the NOAA Vessel OSCAR DYSON,”” Noise Control Engineering Journal, 54(4), JulNoise Control Engineering Journal, 54(4), Jul--Aug., 2006.Aug., 2006.““Shipboard Noise Predictions for Naval Architects,Shipboard Noise Predictions for Naval Architects,”” EuroNoiseEuroNoise 2006, Finland, May 2006.2006, Finland, May 2006.““Elements of a Successful Ship Noise Control Project,Elements of a Successful Ship Noise Control Project,”” ASNE, Marine Environmental Engineering Technology ASNE, Marine Environmental Engineering Technology Symposium 2006, Washington DC, Jan. 2006.Symposium 2006, Washington DC, Jan. 2006.““Factors Affecting the Underwater Noise of Commercial Vessels OpeFactors Affecting the Underwater Noise of Commercial Vessels Operating in Environmentally Sensitive Area,rating in Environmentally Sensitive Area,””(with Neal Brown) Oceans (with Neal Brown) Oceans ’’05, MTS/IEEE Conference, Washington DC, Sept. 2005.05, MTS/IEEE Conference, Washington DC, Sept. 2005.““Acoustic Design, Construction and Testing of Acoustic Design, Construction and Testing of NOAANOAA’’ss Fisheries Research Vessel,Fisheries Research Vessel,”” Lloyds Conference on Ship Lloyds Conference on Ship Noise and Vibration, June 20Noise and Vibration, June 20--21, 2005.21, 2005.““Case Study: Application of SEA to Predicting Shipboard Noise,Case Study: Application of SEA to Predicting Shipboard Noise,”” Lloyds Conference on Ship Noise and Vibration, Lloyds Conference on Ship Noise and Vibration, June 20June 20--21, 2005.21, 2005.““Verification of a Hybrid Model for Shipboard Noise Predictions,Verification of a Hybrid Model for Shipboard Noise Predictions,”” (with Won(with Won--Ho Ho JooJoo, and , and JongJong--Hyun Park), Hyun Park), InterNoiseInterNoise 03, Inst. of Noise Control Engineers, Korea, Aug., 2003.03, Inst. of Noise Control Engineers, Korea, Aug., 2003.““Shipboard Noise Prediction Program Shipboard Noise Prediction Program –– JERICHO,JERICHO,”” (with Kurt Yankaskas) (with Kurt Yankaskas) NoiseConNoiseCon 03, Inst. of Noise Control 03, Inst. of Noise Control Engineers (INCE), Cleveland, June 23, 2003.Engineers (INCE), Cleveland, June 23, 2003."Control of Diesel Induced Shipboard Noise by the Use of Isolati"Control of Diesel Induced Shipboard Noise by the Use of Isolation Mounts," Invited paper, Interon Mounts," Invited paper, Inter--Noise 2001, The Noise 2001, The Hague, Aug. 27Hague, Aug. 27--30, 2001.30, 2001."SEA Application to Shipboard Noise," presented at the First Int"SEA Application to Shipboard Noise," presented at the First International ernational AutoSEAAutoSEA Users Conference, July 27, Users Conference, July 27, 2000, San Diego, CA.2000, San Diego, CA."An Introduction to Statistical Energy Analysis", (with Courtney"An Introduction to Statistical Energy Analysis", (with Courtney Burroughs and Fred Kern), 101(4), Journal of the Burroughs and Fred Kern), 101(4), Journal of the Acoustical Society of America, April 1997.Acoustical Society of America, April 1997.““Noise and Vibration Control Program for the M/V Sulfur EnterprisNoise and Vibration Control Program for the M/V Sulfur Enterprise,e,”” NoiseNoise--Con 96, Seattle WA, Sept. 1996.Con 96, Seattle WA, Sept. 1996."Case History: Excessive Noise and Vibration Induced by Cantile"Case History: Excessive Noise and Vibration Induced by Cantilever Foundations on Ships," Noise Control ver Foundations on Ships," Noise Control Engineering Journal, 31 (3), NovemberEngineering Journal, 31 (3), November--December, 1988.December, 1988.

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