Engineering noise controls

D. A. Bies and C. H. Hansen, Engineering Noise Control Theoy and Practice, Unwin Hyman Ltd., London, 1988. 

Song, X.-R. C., Experimental study of combustion noise generated by oxygen-fuel burners, in Proceedings of the 1993 National Conference on Noise Control Engineering Noise Control in Aeroacoustics, Williamsburg, VA, 1993, 97-102. 

Few would dispute that engineering noise controls involve a high level of expertise. Mismatched vibration isolators could set up a sympathetic reaction and bounce a machine off its mounts. Noise absorbing coefficients of sound insulation have to be matched to the spectrum of the noise. Noise treatment of duct work has to take into account required air flow. But what about other measures like testing hearing and issuing earplugs ... 

Space limits a complete listing of all 16 questions and, unfortunately, military website restrictions preclude a reference to access. Three of the 16 questions and implementation levels in areas of hazard posting, engineering noise controls and hearing protection are included below for a general sense of this concept. Most military unique references have been deleted and minor reconstruction of some levels was necessary to demonstrate this concept for private sector application. Each level should be understood to contain all positive factors in the level below it. 

This chapter includes basic information about the measurement, evaluation, and control of noise at industrial plants. It does not provide cookbook solutions for controlhng noise. Rather, engineering noise control information is based on the authors experience gained from acoustical consulting practice. 

Bies, D.A. Hansen, C.H. 2003. Engineering noise control, London, Spon Press. 

L. L. Beranek, Noise and Vibration Control, Institute of Noise Control Engineering, Cambridge, Mass., 1988. 

A. Thumaim and R. Miller, Fundamentals of Noise Control Engineering, 2nd ed.. The Fairmont Press, Inc., Lilbum, Ga., 1990. 

Jensen, P. Noise control. In Handbook of Environmental Engineering, Volume 1, Air and Noise Pollution Control Wang, L.K., Pereira, N.C., Eds. Clifton, NJ 1979, 411-474. 

NOISE CONTROL. The design engineer should include noise studies in the design stage of any industrial facility. Generally, acoustical problems left for field resolution cost roughly twice as much. Unnecessary costs incurred in post-construction noise work may include the replacement of insulation, re-... 

Sattinger, S. S. in The Role of Damping in Vibration and Noise Control, American Society of Mechanical Engineers Technical Publication H00405, 1987 pp. 33-40. 

Aircraft panels, appendages, turbine-engine components, fuselage skin panels acoustic fatigue, noise control... 

T. Dear, Ammonia plant operations. .. gas handling noise control, Chem. Engin. Prog. 70(2), 65, Feb. 1974. 

Much of the research on advanced fuel synthesis and characterization, fundamentals of combustion, and early work on combustion control and emissions and plumes were covered in the recent book, Advances in Chemical Propulsion Science to Technology [1]. Some of the accomplishments that were not included, the progress made in Combustion Control since this publication and in the new areas of pulse detonation engines and high-speed jet noise control (over the past five years), have been reviewed. A number of these research efforts and the new scientific accomplishments and contributions are presented in this book. 

Liu, D. H. F. "6.7 Noise Control in the Transmission Path." In Environmental Engineers Handbook, edited by... 

Gharabegian, A., and Peat, J. E. "Saudi Petrochemical Plant Noise Control." Journal of Environmental Engineering 112, no. 6 (1986) 1026 0. 

Maling, Jr., J. G., ed. "Start-Up ilencers for a Petrochemical Gomplex," Proceedings of International Conference of Noise Control Engineering, December 3-5,1984. 

Thurman, A., and Miller, R. K., Fundamentals of Noise Control Engineering, Fairmont Press, Atlanta, GA (1986). 

As designed, the RP blades are essentially hollow with an internal rib structure. These rib like vents direct, mix, and control airflow more effectively which reduces the amovmt of energy needed to turn the blades and cuts back on noise. Most engine noise actually comes fi-om wind turbulence that collides with the nacelle. By directing air out the back of the fan blades, the noise can be reduced by a factor of two. And by drawing more air into the blades, engine efficiency is improved by 20%. 

Noise controls—steps are to be taken to control noise at the source. Noise controls are required in situations where the noise level exceeds 90 dBA. Administrative controls are sufficient until noise levels exceed 100 dBA. Beyond 100 dBA, engineering controls must be used. 

Engineering measures aimed at the reduction of noise at the source precluding the propagation, amplification, and reverberation of noise and isolating workers. The term is meaningful only when noise control components and the points of observation are fully specified. 

It is important to know the sound transmission loss of walls and floors in order to be able to compare different constructions, to calculate acoustic privacy between apartments or noise levels from outdoor sources such as road traffic, and to engineer optimum solutions to noise control problems. Laboratory measurements can be made for many different types of partitions, but it is impractical to test every possible design, and so it is necessary to have reliable methods for predicting the sound transmission loss of typical building constructions. 

There are various methods for predicting the soimd transmissirMi loss of walls and floors that can be used by noise control engineers. It is important to know how accurate these methods are for typical constmctions used in building acoustics (Ballagh 2004). As the standard grows in experience over the years, it reveals the complex variables that must be addressed in order to equalize the conditions that have a potential to affect results. 

K.O. Ballagh, in The 33rd International Congress and Exposition on Noise Control Engineering, August 22-25 (Prague, 2004)... 

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