Double wall sound shield with modular sound absorbent panels for an air core reactor

A method of attenuating noise generated within an air-core reactor, the method comprising:

• providing upper and lower spider units each comprising a plurality of support arms extending radially outward from a central axis;
• providing a coil including a plurality of cylindrically shaped winding layers concentrically positioned about one another and with respect to the central axis, the plurality of cylindrically shaped winding layers including an outermost layer;
• and
• providing a double wall sound shield including concentric a first roving cylinder and a second roving cylinder, the first roving cylinder positioned against the outermost layer but detached from the coil by a first airgap between the outermost layer and the first roving cylinder to reduce a structure-borne transmission of an acoustic energy or attached by ductsticks to the coil,
• wherein the second roving cylinder is placed at a distance from the first roving cylinder to form an acoustic cavity between two double walls of the first roving cylinder and the second roving cylinder,
• wherein the double wall sound shield further includes a plurality of sound absorbent panels to attenuate resonances of the acoustic cavity between the two double walls of the first roving cylinder and the second roving cylinder, and
• wherein the plurality of sound absorbent panels comprises a layer of sound absorbing material and each of the plurality of sound absorbent panels is separated from the first roving cylinder by a second airgap.