Induced Noise Control
Abstract
The induced noise control parameter is defined in terms of the ratio of the stored energy in a master dynamic system, when it is coupled to an adjunct dynamic system, to that stored energy when the coupling is absent. An induced noise control parameter comprises of two factors. The first is defined in terms of the ratio of the indigenous loss factor of the master dynamic system to the virtual loss factor. The virtual loss factor is the sum of the indigenous loss factor of the master dynamic system and the induced loss factor. The induced loss factor measures the influence of an adjunct dynamic system that is coupled to the master dynamic system. The first factor is, then, by definition less than unity. The second factor is defined in terms of the ratio of the external input power into the master oscillator, when coupled, to the external input power in the absence of this coupling. This second factor, which is positive definite, may either exceed unity, be unity, or be less than unity. Both factors in the induced noise control parameter, however, are critically dependent on the global coupling strength. The global coupling strength is again, a ratio. This ratio is that of the energy stored in the adjunct dynamic system and in the coupling to the energy stored in the master dynamic system. The investigation of this ratio and its relationship to the induced loss factor is explained and graphically illustrated. The modal coupling strength is determined via the global coupling strength. In the statistical energy analysis (SEA) the value of the modal coupling strength, by definition, lies below unity. In the energy analysis (EA) herein developed, the modal coupling strength may exceed unity. This excess occurs in the energy analysis (EA) when the coupling is strong and the damping assigned to the adjunct dynamic system is low. The damping in the adjunct dynamic system is conveniently defined in terms of an associated modal overlap parameter.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2002
- Accession Number
- ADA406507
Entities
People
- Gideon Maidanik
- K. J. Becker
Organizations
- Naval Surface Warfare Center Carderock Division