Shipboard acoustics : proceedings of the 2nd international symposium on Shipboard Acoustics, ISSA '86, the Hague, the Netherlands, October 7-9, 1986

The first International Symposium on Shipboard Acoustics, held in Noordwijkerhout (The Netherlands) in 1976, was a meeting of invited experts, each having considerable expertise in ship acoustics. Many of the participants were dealing with research on various ship acoustical subjects, and it proved to be a good idea to discuss future investigations and new techniques. At that time acousticians learned to use real-time signal-processing techniques and attempts were made to establish sound level prediction methods based on semi-fundamental considerations instead of the methods using empirically obtained data. Time was pressing as it was assumed that, in view of the adoption of Recommendation 141 of the International Labour Conference in 1970, authorities would soon make appropriate provisions to "protect seafarers from the ill effects of noise". This resulted in several national recommendations followed by the IMO "Code on noise levels aboard ships" which was adopted by the IMO Assembly in 1981. After that, pressure on the authorities was increased further by the decision of the European Community to protect labourers against harmful noise at their workplaces, including ships. Legally enforceable noise limits will therefore become normal in the future. In many countries recommendations with respect to maximum allowable sound pressure levels in the crew accomodations and work area aboard ships were already taken into account by ship owners, long before the existence of the Recommendations. Front Matter....Pages I-IX Front Matter....Pages XI-XI Prediction Method for the Acoustic Source Strength of Propeller Cavitation....Pages 1-19 Propeller Induced Noise and Vibration Reduction: Acquired Experience in Design and Testing Approach....Pages 21-42 Experimental and Analytical Aspects of Propeller Induced Pressure Fluctuations....Pages 43-62 Model and Full Scale Measurements of Propeller Cavitation Noise on an Oceanographic Research Ship with Two Different Types of Screw Propeller....Pages 63-74 A Study of Simulation and Elimination of Propeller Singing....Pages 75-90 Propeller Noise: Some Topics from the Activities of Brodarski Institute....Pages 91-102 Some Experiments on the Transmission of Propeller Cavitation Noise into the Ship’s Structure....Pages 103-119 Quiet High-Speed Yachts and Water Jet Applications....Pages 121-133 Model-Scale Measurements of the Transmission and Radiation of Hull-Borne Vibrational Energy Using Frequency/Wavenumber Analysis....Pages 135-154 Underwater Noise Radiation Due to Transmission through the Cooling Water System of a Marine Diesel Engine....Pages 155-175 Measurements of Underwater Acoustic Intensity in the Nearfield of a Point Excited Periodically Ribbed Cylinder....Pages 177-188 Sound Generation from a Moving Shell....Pages 189-199 Low Noise Levels as the First Task of a Vessel. A Description and Some Remarks about Acoustic Quieting Design Criteria and Features of Saclant ASW Centre Oceanographic Research Vessel....Pages 201-215 Ship Noise Criteria. Do They Reflect the Present Level of Noise Reduction Technology?....Pages 217-232 A Literature Survey Concerning Propeller as a Noise Source and Prediction Methods of Structure-Borne Noise in Ships....Pages 233-243 Applications of Two Mathematical Approaches to Predict Airborne Noise Levels in Ship Superstructures....Pages 245-263 Some Observations on the Achievable Properties of Diesel Isolation Systems....Pages 265-278 Acoustic Transfer Functions of Flexible Shaft Couplings....Pages 279-294 Random Vibration of Multiterminal Mechanical Systems....Pages 295-315 The Influence of the Internal Impedance on Vibration Reduction....Pages 317-333 Front Matter....Pages XI-XI Main Propulsion Diesel Generator Sets with Acoustic Enclosure and Double Resilient Mounting for Low Noise Application....Pages 335-351 Flexural Wave Damping in Ship Hulls, Decks and Bulkheads....Pages 353-364 Determination of Acoustic Properties of Ship’s Sound Reducing Floors....Pages 365-375 Study of Structure-Borne Noise Transmission Inside Cabins by Sound-Intensity Measurements....Pages 377-391 Experiments on Sound Reducing Floors Including Visco-Elastic-Damping on Board a Rhine Cruise Vessel....Pages 393-416 Noise Reduction of Bow Thrusters....Pages 417-432 Noise Prediction and Prevention....Pages 433-459 Review on the Results of Ten Years of Ship Acoustic Research in the Netherlands....Pages 461-481 Front Matter....Pages 483-483 Some comments on the paper: Prediction Method for the Acoustic Source Strength of Propeller Cavitation....Pages 485-487 Discussion on the paper given by: Dr. A. de Bruijn, W.H. Moelker, Dr. F.G.J. Absil: Prediction Method for the Acoustic Source Strength of Propeller Cavitation....Pages 488-491 Discussion on the paper given by: Dr. A. Colombo, P. Ausiono, L. Grossi and L. Accardo: Propeller Induced Noise and Vibration Reduction: Acquired Experience in Design and Testing Approach....Pages 493-493 Discussion on the paper given by: J. van der Kooij: Experimental and Analytical Aspects of Propeller Induced Pressure Fluctuations....Pages 495-497 Discussion on the paper given by: T. Sasajima, N. Nakamura and A. Oshima: Model and Full Scale Measurements of Propeller Cavitation Noise on an Oceanographic Research Ship with Two Different Types of Screw Propeller....Pages 499-501 Discussion on the paper given by: Dr. B. Bajić: Propeller Noise: Some Topics of the Activities of Brodarski Institute....Pages 503-503 Discussion on the paper given by: J.H. Janssen and W.H. Moelker: Some Experiments on The Transmission Of Propeller Cavitation Noise Into The Ship’s Structure....Pages 505-505 Comments on the Paper “Some Experiments on the Transmission of Propeller Cavitation Noise into the Ship’s Structure”....Pages 506-512 Discussion on the paper given by: J.I. Smullin: Quiet High-Speed Yachts and Waterjet Applications....Pages 513-516 Discussion on the paper given by: J.R. Chapman: Model-Scale Measurements of the Transmission and Radiation of Hull-Borne Vibrational Energy Using Frequency/Wavenumber Analysis....Pages 517-519 Discussion on the paper given by: Dr. M. Purshouse (represented by Mr. D.J. Rothwell): Underwater Noise Radiation Due to Transmission through the Cooling Water System of a Marine Diesel Engine....Pages 521-523 Discussion on the paper given by: Dr. A.R. Clark and P.S. Watkinson: Measurements of Underwater Acoustic Intensity in the Near-Field of a Point Excited Periodically Ribbed Cylinder....Pages 525-525 Front Matter....Pages 483-483 Discussion on the paper given by: Zhu Xiqing: Sound Generation from a Moving Shell....Pages 527-528 Discussion on the paper given by: E. Bonetti and P. Calgano: Low Noise Levels as the First Task of a Vessel. A Description and Some Remarks about Acoustic Quieting Design Criteria and Features of Saclant ASW Centre Oceanographic Research Vessel....Pages 529-530 Discussion on the paper given by: J. Ødegaard: Ship Noise Criteria, do they Reflect the Present Level of Noise Reduction Technology?....Pages 531-533 Addendum given by the author to the paper: A Literature Survey Concerning Propeller as a Noise Source and Prediction Methods of Structure-Borne Noise in Ships....Pages 535-540 Discussion on the paper given by: P. Hynnä: A Literature Survey Concerning Propeller as a Noise Source and Prediction Methods of Structure-Borne Noise in Ships....Pages 541-543 Discussion on the paper given by: P. Calcagno, R. Maltese and F. Pinazzi: Applications of Two Mathematical Approaches to Predict Airborne Noise Levels in Ship Superstructures....Pages 545-546 Discussion on the paper given by: Dr. R. Kinns: Some Observations on the Achievable Properties of Diesel Isolation Systems....Pages 547-548 Discussion on the paper given by: Ir. J.G. van Bakel: Acoustic Transfer Functions of Flexible Shaft Couplings: Measurement Method and Results....Pages 549-551 Discussion on the paper given by: Dr. A.O. Sykes: Random Vibration of Multiterminal Mechanical Systems....Pages 553-554 Discussion of the paper given by: Dr. P. Tilmann: The Influence of the Internal Impedance on Vibration Reduction....Pages 555-556 Discussion on the paper given by: G. Mancuso and F. Sacchi: Main Propulsion Diesel Generator Sets with Acoustic Enclosure and Double Resilient Mounting for Low Noise Application....Pages 557-558 Discussion on the paper given by: Dr. B.E. Douglas: Flexural Wave Damping in Ship Hulls, Decks and Bulkheads....Pages 559-560 Discussion on the paper given by: S. Weyna: Determination of Acoustic Properties of Ship’s Sound Reducing Floors....Pages 561-562 Discussion on the paper given by: Mrs. A. Blanchet, Mr. G. Chatel and Mr. A. Paradis: Study of Structure-Borne Noise Transmission Inside Cabins by Sound- Intensity Measurements....Pages 563-563 Discussion on the paper given by: M.J.A.M. de Regt: Experiments on Sound Reducing Floors Including Visco-Elastic Damping on Board A Rhine Cruise Vessel....Pages 565-566 Discussion on the paper given by: Dr. A.C. Nilsson: Noise Reduction of Bow Thrusters....Pages 567-568 Discussion on the paper given by: K. Andresen, Dr. A.C. Nilsson and E. Brubakk Noise Prevention and Reduction....Pages 569-570 Discussion on the paper given by: J. Buiten: Review on the Results of Ten Years of Ship Acoustic Research in the Netherlands....Pages 571-571 Back Matter....Pages 573-576