The transmissibility of thin, simply supported, rectangular aluminum plates of like dimensions has been determined experimentally in the frequency range 25–3025 Hz. Comparison has been made between the results of mea...
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The transmissibility of thin, simply supported, rectangular aluminum plates of like dimensions has been determined experimentally in the frequency range 25–3025 Hz. Comparison has been made between the results of measurements on an unloaded plate, on plates loaded centrally by concentrated masses of small and large contact area, and on plates loaded by seven different straight‐rib configurations, one of which utilized X‐cut ribs that stretched diagonally between opposite plate corners. The additional mass was always equal to that of the plates so that the effectiveness of the mass in reducing transmissibility could be evaluated as a function of its geometry. The experimental transmissibilities of the unloaded and centrally mass‐loaded plates were in excellent agreement with theoretical prediction. At frequencies above the fundamental resonance of the plates, the greatest overall reduction in transmissibility was provided by the X‐cut ribs; whereas, at the fundamental resonance itself, the greatest reduction was provided by a single central rib placed parallel to the shorter plate sides. Subject Classification: [43]40.24, [43]40.20.
The transmissibility across thin, simply supported, rectangular, and square aluminum plates has been determined experimentally and found to agree closely with theoretical prediction through the frequency range of meas...
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The transmissibility across thin, simply supported, rectangular, and square aluminum plates has been determined experimentally and found to agree closely with theoretical prediction through the frequency range of measurement, which extended from 25 to 3025 Hz. Both the rectangular and the square plates considered were uniquely supported by spring‐steel flanges, which were designed to provide, for the first time, true simple supports that simulated almost identically the idealized supports assumed as boundary conditions in theoretical analyses for more than a century. For example, the first 20 resonant frequencies of the rectangular plate with these novel supports differed, with only one exception, by less than 0.55% from their predicted values. One important result obtained for the damped plates considered—which comprised aluminum plates plus applied tiles of high‐damping compound to yield composite plates having damping factors of essentially 0.3—was that the measured transmissibility across the plates could be duplicated closely by an expression for transmissibility developed for an internally damped homogeneous plate having damping factors equal to those of the composite plates. Subject Classification: 40.24, 40.60, 40.20.
The transmissibility across rectangular, simply supported, thin plates vibrating transversely has been measured experimentally through the frequency range 25–3025 Hz. Good success has been achieved in obtaining simpl...
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The transmissibility across rectangular, simply supported, thin plates vibrating transversely has been measured experimentally through the frequency range 25–3025 Hz. Good success has been achieved in obtaining simply supported plate boundaries; the design of these followed directly from a preliminary study of several “simple supports” for long thin beams. Transmissibility has been measured across plates with concentrated mass loadings and with ten combinations of straight or circular rib loadings. In each case, the total added mass equalled the plate mass. Measurements were also made on plates coated by damping tile. Very favorable agreement between the experimental results and theory has been found in those cases where comparison could be made; namely, between the transmissibilities of unloaded plates, damped plates, and centrally mass‐loaded plates [J. C. Snowdon, J. Acoust. Soc. Am. 56, 1177–1184 (1974)]. Choice of the most suitable mass or rib geometries for overall attenuation of transmissibility is discussed, together with choice of the most effective rib geometry with which to attenuate any one resonant peak. [Investigation supported by the Naval Sea Systems Command.]
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