Nozzles for amplifying and suppression of sound

An acoustic nozzle [2.A, 2.B, 2.C, 3.A];

• the acoustic nozzle comprising a solid corpus submerged in fluid and exposed to sound, audible or ultrasonic, propagating in the fluid;
• said solid corpus comprising an inner canal having:
• an open sound-inlet having a sound-inlet cross-sectional area, indicated by AIN;
• an open sound-outlet having a sound-outlet cross-sectional area, indicated by AOU;
• and
• a varying cross-sectional area, varying along the canal length, thereby, forming a shaped through-hole tunnel-waveguide being either converging, divergent, convergent-divergent, divergent-convergent, two-stage convergent-divergent;
• wherein:
• an M-velocity is defined as a velocity measured in Mach numbers;
• and
• a sound is specified as a complicated movement of molecules of the fluid, wherein the complicated movement comprising motion components as follows:
• the Brownian motion of the molecules of the fluid;
• an oscillating motion of the molecules of the fluid, wherein the oscillation motion occurs with an oscillating particle velocity;
• a conveying motion of a tiny mass of the fluid in a direction of sound propagation;
• the tiny mass is the positive and negative changes in the mass density which is a result of the oscillating motion of the molecules, specifically synchronized in phase such that providing headway motion of the positive and negative changes in fluid mass density in the direction of the sound propagation, wherein the conveying motion of the tiny mass of the fluid occurring with a velocity of sound in the fluid;
• and
• turbulent motion of groups of the molecules of the fluid;
• wherein:
• the open sound-inlet is exposed to ambient sound entering into and propagating within the inner canal and, thereby, the fluid within the shaped through-hole tunnel-waveguide is subjected to the propagating sound performing a complicated movement of the fluid;
• the shaped through-hole tunnel-waveguide is characterized by a cross-sectional area profile smooth function A(x) of x-coordinates, where the x-coordinates are defined as increasing in a direction of sound propagation;
• wherein at least one portion, either converging, divergent, or convergent-divergent, of the shaped through-hole tunnel-waveguide, is characterized by a cross-sectional area profile function ANOZZLE(x), specified as a reference equation expressed as:
• A
• NOZZLE
• (
• x
• )
• =
• A
• *
• M
• ⁡
• (
• x
• )
• ⁢
• (
• γ
• -
• 1
• γ
• )
• 1
• 2
• ⁢
• (
• 2
• +
• γ
• ⁡
• (
• M
• ⁡
• (
• x
• )
• )
• 2
• γ
• +
• 1
• )
• γ
• +
• 1
• 2
• ⁢
• (
• γ
• -
• 1
• )
• ,
• x
• a
• <
• x
• <
• x
• b
• where γ is an adiabatic compressibility parameter of a portion of fluid, xa and xb are x-coordinates of the portion's beginning and end, correspondingly, M(x) is a gradual smooth function of x representing a profile of an M-velocity of a tiny mass of the fluid motion within the shaped through-hole tunnel-waveguide, and A* is a constant satisfying a condition
• A
• IN
• A
• *
• ≥
• (
• γ
• -
• 1
• γ
• )
• ⁢
• (
• 2
• +
• γ
• γ
• +
• 1
• )
• γ
• +
• 1
• (
• γ
• -
• 1
• )
• ;
• thereby, providing for that the acoustic nozzle functions as either:
• a sound-booster, to:
• solve a problem of sound power dissipation into heat energy of fluid,
• convey the sound from the open sound-inlet to the open sound-outlet, and
• amplify loudness of the sound at the expense of both the heat energy of fluid and concomitant turbulence of the fluid;
• or, contrariwise,
• a sound-silencer, to suppress a waveguide effect and transform the sound's intensity into ambient heat thereby solving a problem of sound propagation.