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Showing 1 to 9 of 9 for “"payload fairing"”.
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Adaptive Collocated Feedback for Noise Absorption in Acoustic Enclosures
… experienced during launch within launch vehicle payload fairings. Two acoustic enclosures are used in the research: the first being a symmetric cylindrical duct and the other being a full scale model of a payload fairing. The symmetric cylindrical duct is used to validate the ability of the …
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Multi-Degree of Freedom Passive and Active Vibration Absorbers for the Control of Structural Vibration
… to reduce structural vibration in a rocket payload fairing. Since the efficiency of acoustic foam is very poor at low frequencies, the target bandwidth was 50 to 200 Hz. A 2DOF active vibration absorber was desired to exhibit broad resonance characteristics over this frequency band. An …
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Design and development of advanced vibration and noise control devices using finite element analysis
… pressure levels (SPL's) radiated inside the payload fairing by its vibrating frame causes 40% of the satellite damage in the initial phases of the launch. Numerous experiments conducted on the advanced vibration absorbers such as the distributed vibration absorbers (DVA's) and the …
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Structural & Internal Acoustic Response of Cylinders with Applications to Rocket Payload Fairings
Future launch vehicle payload fairings will be manufactured from advanced lightweight composite materials. The loss of distributed mass causes a significant increase in the internal acoustic environment, causing a severe threat to the payload. Using piezoelectric actuators to control the fairing …
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Acoustic Devices for the Active & Passive Control of Sound in a Payload Compartment
… loudspeakers used for noise control in rocket payload compartments are developed. Second, active control using a hybrid control system (with structural and acoustic actuators) was tested experimentally. Due to the weight limitations for this application, Helmholtz resonators and loudspeakers …
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Control of sound transmission into payload fairings using distributed vibration absorbers and Helmholtz resonators
… treatment to reduce sound transmission into payload fairing at low frequency is investigated. This new solution is composed of optimally damped vibration absorbers (DVA) and optimally damped Helmholtz resonators (HR). A fully coupled structural-acoustic model of a composite cylinder excited …
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Piezoceramic Actuated Transducers for Interior Acoustic Noise Control
… are on the order of 10,000 dollars per pound of payload capacity. Reducing weight and thus increasing payload capacity is always in the forefront of the design process. One method of increasing the payload capacity of launch vehicles is to reduce the acoustic environment in the interior of the …
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Modal and Impedance Modeling of a Conical Bore for Control Applications
… lowering acoustic levels within launch vehicle payload fairings. Due to the predominance of conical geometries within payload fairings, our work focused on the analytical modeling of conical shrouds using modal and impedance based models. Incorporating an actuating boundary condition within a …
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Control of Sound Transmission with Active-Passive Tiles
Nowadays, numerous applications of active sound transmission control require lightweight partitions with high transmission loss over a broad frequency range and simple control strategies. In this work an active-passive sound transmission control approach is investigated that potentially addresses …