Noise vibration control

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

Catalog of STC andllC Ratings for Wall andEloorj Ceiling Assemblies, Office of Noise Control, California Department of Health Services, Berkeley, Calif., 1984. R. S. Jones, Noise and Vibration Control in Buildings, McGraw-HiU Book Co., Inc., New York, 1984. 

Across a control valve the fluid is accelerated to some maximum velocity. At this point the pressure reduces to its lowest value. If this pressure is lower than the liquid s vapor pressure, flashing will produce bubbles or cavities of vapor. The pressure will rise or recover downstream of the lowest pressure point. If the pressure rises to above the vapor pressure, the bubbles or cavities collapse. This causes noise, vibration, and physical damage. 

The most frequently encountered flashing problems are in control valves. Downstream from the control valve a point of lowest pressure is reached, followed by pressure recovery. A liquid will flash if the low pressure point is below its vapor pressure. Subsequent pressure recovery can collapse the vapor bubbles or cavities, causing noise, vibration, and physical damage. 

The desirable operating characteristics of equipment include simplicity, convenience and low cost of maintenance simplicity, convenience and low cost of assembly and disassembly convenience in replacing worn or damaged components ability to control during operation and test before permanent installation continuous operation and steady-state processing of materials without excessive noise, vibration or upset conditions a minimum of personnel for its operation and, finally, safe operation. Low maintenance often... 

Whole body Variety and number of animals Chronic studies possible Minimum restraint Large historical database Controllable environment Minimum stress Minimum labor Messy Multiple routes of exposure skin, eyes, oral Variability of dose Cannot pulse exposure easily Poor contact between animals and investigators Capital intensive Inefficient compound usage Difficult to monitor animals during exposure Cleaning effluent air Inert materials Losses of test material Even distribution in space Sampling Animal care Observation Noise, vibration, humidity Air temperature Safe exhaust Loading Reliability... 

Ungar, E.E. "Damping of Panels," in "Noise and Vibration Control," L. L. Beranek, Ed., McGraw-Hill, New York, 1971, Ch. 14. 

Commerce appliances, office machines, computer components, metal cabinets, and furniture noise and vibration control... 

Ungar, E. E. In Noise and Vibration Control Beranek, L. L., Ed. McGraw-Hill New York, 1971 Chapter 14. Mead, D. J. Criteria for Comparing the Effectiveness of Damping Treatments Report No. 125 Department of Aeronautics and Astronautics, University of Southampton Hampshire, England, 1960. 

Henderson, J.P. and M.L. Drake, "Investigation of the Effects of Damping Treatments on the Response of Heated Fuselage Structure," NoisEXPO, National Noise and Vibration Control Conference, New York, New York, March, 1976. 

This book provides an advanced level of study of industrial hygiene engineering situations with emphasis on the control of exposure to occupational health hazards. Primary attention is given to industrial ventilation, noise and vibration control, heat stress, and industrial illumination. Other topics covered include industrial water quality, solid waste control, handling and storage of hazardous materials, personal protective equipment, and costs of industrial hygiene control. 

Warring, R. H. (1974) Handbook of Noise and Vibration Control, 2nd edn (Trade and Technical Publications). Wells, G. L. (1980) Safety in Process Plant Design (IChemE/Godwin). 

However, besides exhaust emission control - Fig. 2 - various other aspects in engine development have to be taken into account. The most challenging parameters for the diesel engine are noise, vibration harshness (NVH) control and the necessary technology versus cost required for competitive performance. 

During this period, additional data is collected, including data associated with motor amperage draw, pump curve performance, interface control, and operational baseline parameters, such as noise, vibration, and performance specifications are initiated. 

Beranek, L., ed. (1971), Noise and Vibration Control, New York, McGraw-Hill. 

Ver, Istvan L., and Leo L. Beranek, eds. Noise and Vibration Control En neering Principles and AppUcor tions. 2d ed. Hoboken, N.J. John Wiley Sons, 2006. Details sound absorption, passive silencers, enclosures, vibration isolation and damping, machinery and heating, ventilation, and air-conditioning (HVAC) noise control, and active noise suppression. 

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