摘要:
Aspects of the invention are directed to a system for improving the damping performance of an acoustic resonator. According to aspects of the invention, a resonator, such as a Helmholtz resonator, can be attached to a surface of a combustor component in a turbine engine. The combustor component includes a region in which a plurality of passages extend through the thickness of the component. The resonator is attached to the component so as to enclose at least some of the passages. The passages are in fluid communication with a cavity defined between the component surface and the resonator. Resonator performance is a function of the length of the passages in the component. According to aspects of the invention, resonator performance can be improved by reducing the length of the passages in the component by reducing the thickness of the component in a region that includes the plurality of passages.
摘要:
A resonator for damping pressure waves or instabilities in a system supported by acoustic energy wherein the resonator adopts the use of counter-bored openings on the downstream side of the resonator within the flow path of the system. The resonator includes a first member and a second member where the second member includes a plurality of openings therethrough with each hole having a counter-bore on its upstream side. The first member has a size substantially smaller than the diameter of said flow path and a first plurality of openings therethrough. The openings are in fluid communication with the flow path. The second member has a size generally equal to the first member and a second plurality of openings therethrough, which openings are in fluid communication with the flow path.
摘要:
A high-volume source for very low frequency applications in which conventional speakers are inadequate is disclosed. A presently preferred embodiment comprises a reservoir 32 with a pressure relief 33; a controller 34; a supply blower 36; an exhaust blower 38; a positive plenum 40; a negative plenum 42; an orifice plate with valving 44; a horn 46; and pressure transducers 48, 50, 52, 54, feeding detected pressure levels to the controller 34. An electrical command signal s(t) is also input to the controller. The command signal is a voltage analogous to the acoustic pressure or volume velocity to be output by the source.
摘要:
A damping system for a fabricated gear comprising a plurality of viscoelastic sheets sandwiched between damping plates and side plates, the side plates having circumferential rings which act as mode converters to change in-plane vibration to bending mode vibrations and are fixed to one margin of the damping plate to provide effective vibration damping within the gear.
摘要:
Under certain conditions, the fuel delivery system can contribute to the formation of strong dynamic pressures in the combustor of a turbine engine. Embodiments of the invention provide a system for dynamically stiffening the fuel supply passage to suppress damaging combustion dynamics. To that end, a Helmholtz resonator can be placed along and in branched relation to the fuel supply passage. The resonator can produce the effect of adding a pressure release opening at a selected location in the fuel line, causing a shift in the fuel line pressure wave pattern that blocks fuel flow fluctuations at the outlet of the fuel passage at the frequency of the oscillation. The pressure wave shift results in a shifting of the volume velocity wave pattern. Ideally, the resonator can be positioned along the flow path such that the volume velocity of the fuel at the fuel passage exit is minimized.
摘要:
An internally damped structure having a thin, segmented layer of high modulus composite material acting as a constraining layer and bonded on both sides to layers of viscoelastic damping layers acting as shear layers. The arrangement forms a triple layer sandwich which is embedded in the wall of the structure. A compliant filler is positioned between adjacent segments of the composite constraining layer.In an alternate embodiment two such sandwich arrangements are embedded in the wall of the structure.
摘要:
A laminated panel is provided by; a reinforced composite core of either an organic matrix or a metal matrix, bonded by at least one layer of adhesively bonded viscoelastic damping polymer film and face sheeting of steel for use as integrally-damped steel/composite laminates in extended ship structures, tanks, tactical mobile field units, mobile computer rooms, seismic equipment support structures or any other load-bearing steel structures utilized in high noise/high vibration environments. Utilization of an organic matrix composite core in the integrally-damped steel/composite laminate provides an effective toxicity and flammability barrier for use in human/machine interfaces. Utilization of a metal matrix composite core in the integrally-damped steel/composite laminate provides an effective flammability barrier. Internally tapered edge adapters to interconnect the laminates to themselves or to other steel structures is also provided.
摘要:
A hollow beam structure such as a machinery subbase having apertures in sidewall portions thereof has a plurality of shear damper assemblies which straddle the apertures and are fastened to the wall portion on opposite sides of the apertures. The shear damper assemblies include a viscoelectric damping layer which dissipates vibrational energy to minimize the vibrational response of the hollow beam structure.
摘要:
A resonator for damping pressure waves or instabilities in a system supported by acoustic energy wherein the resonator adopts the use of counter-bored openings on the downstream side of the resonator within the flow path of the system. The resonator includes a first member and a second member where the second member includes a plurality of openings therethrough with each hole having a counter-bore on its upstream side. The first member has a size substantially smaller than the diameter of said flow path and a first plurality of openings therethrough. The openings are in fluid communication with the flow path. The second member has a size generally equal to the first member and a second plurality of openings therethrough, which openings are in fluid communication with the flow path.
摘要:
A resonator module for a combustion turbine power plant, where the combustion turbine power plant defines a flow path. The resonator module includes a first member, an a second member. The first member has a size substantially smaller than the diameter of said flow path and a plurality of openings therethrough. The openings are in fluid communication with the flow path. The second member has a size generally equal to said first member. The second member is in a generally spaced relation to the first member and encloses a volume of gas between the first and second members.