DUAL RESONATOR CHAMBER WITH VARIABLE VOLUME

摘要

The dual resonator chamber with variable volume includes first and second housings. The second housing is slidably mounted within the first housing such that a second inner neck portion of the second housing is slidably mounted about the first inner neck portion of the first housing and forms a fluid-tight seal therewith. A sliding wall is slidably mounted within the second housing, dividing the interior thereof into upper and lower resonator chambers. At least one first actutator selectively adjusts the height of the sliding wall with respect to the second lower end of the second housing to selectively adjust volumes of the upper and lower resonator chambers. At least one second actuator selectively adjusts the height of the second housing with respect to the first housing to selectively adjust the neck length of the lower resonator chamber.

主权项

1. A method of controlling a resonator chamber with variable volume, comprising the steps of:
(a) recording a resonant frequency f to be attenuated in non-transitory computer readable memory; (b) randomly selecting a dimensionless area ratio λ in the range of 0.1<λ<1.0, whereinλ=A2A1,  A2 being a cross-sectional area of a neck of a resonator chamber and A1 being a cross-sectional area of a primary chamber of the resonator chamber; (c) establishing a first length parameter L1 associated with a height of the primary chamber having a maximum value L1max given byL1max=0.2756cf,  where c is the speed of sound and L1=L1max−Δ, where Δ is an optimization parameter; (d) establishing a second length parameter L2 associated with a height of the neck of the resonator chamber, whereinL2=1ktan-1(λtan(kL1)); (e) maximizing a transmission loss TL of the resonator chamber in terms of the optimization parameter Δ to determine a maximized parameter Δmax which maximizes the transmission loss, whereinTL=10log10[1+(A22A3×(1λ)tan(kL1)+tan(kL2)(1λ)tan(kL2)tan(kL1)-1)2]; (f) calculating the first length parameter L1 as L1=L1max−Δmax; (g) calculating the second length parameterL2asL2=1ktan-1(λtan(k(L1max-Δmax))); (h) if TL is not maximized for for all possible values of λ in the range 0.1<λ<1.0, then returning to step (b), otherwise calculating the height of the primary chamber H1 as H1=L1 and calculating the height of the neck of the resonator chamber H2 as H2=L2−δ1−δ2, where δ2 is a design parameter given by δ2=0.48√{square root over (A2)}(1−1.25√{square root over (λ)}) and δ1 is a design parameter given byδ1=0.46A22;  and (i) transmitting a control signal to adjust the height of the primary chamber to H1 and the height of the neck of the resonator chamber to H2.