COOLING DEVICE WITH LOW NOISE LEVEL Russian patent published in 2013 - IPC F04D33/00 H01L23/467 H05K7/20 

FIELD: machine building.

SUBSTANCE: cooling device 1, using a pulsating fluid medium for object cooling, comprising the following: a converter 2, having a membrane made as capable of generation of pressure waves with working frequency f_w; and a cavity 4, which holds the first side of the membrane. The cavity 4 has at least one hole 5, which is made as capable of emission of a pulsating flow of the fluid medium minus the losses to the specified object, at the same time the opening 5 communicates with the second side of the membrane. The cavity 4 is quite small to prevent action of the fluid medium in the specified cavity 4 as a spring in the resonating mass-spring system in the operating range. This is an advantage, since the volume speed u₁ around the hole is substantially equal to the volume speed u₁ near the second side of the membrane, excluding the minus sign. Thus, at the working frequency the pulsating fluid medium minus the losses may be to a considerable extent suppressed due to the antiphase of pressure waves at the second side of the membrane, causing as a result the volume speed close to zero in the remote area.

EFFECT: low sound level at low cost and without necessity to provide mechanical symmetry.

10 cl, 6 dwg