Sound absorber and wheel having same

A sound absorber, being mounted on a moving component in an air environment to reduce acoustic resonance, wherein the sound absorber is configured as a rectangular hexahedral box and forms a porous double-layer Helmholtz resonance sound absorbing structure, the box has two sides including a first side and a second side opposite to the first side, defining boundaries of two ends of the box in the moving direction of the moving component, the inside of the box is divided by a partition into a first cavity and a second cavity successively arranged in the moving direction of the moving component, the partition is parallel to the first side of the box, two hollow tubes are mounted on the first side, each hollow tube mounted on the first side has an orifice opened to a wheel air chamber on the first side and has an elongated structure and extends into the first cavity at a distance corresponding to each length in a direction of the longest axis of the rectangular hexahedral box, a hollow tube is mounted on the partition and has an orifice opened to the first cavity on the partition and has an elongated structure and extends into the second cavity at a distance corresponding to its length in a direction of the longest axis of the rectangular hexahedral box, and the longest axis of each hollow tube mounted on the first side and the partition extends along the longest axis of the rectangular hexahedral box, and the first cavity and the second cavity constitute two layered resonant cavities of the porous double-layer Helmholtz resonance sound absorbing structure;

• wherein a plane of the orifice opened to the first cavity of the hollow tube mounted on the partition is on the same surface as the partition in the box;
• wherein the orifice of each hollow tube opened to the wheel air chamber on the first side is smaller than the orifice of the hollow tube opened to the first cavity on the partition.