Aerodynamic noise reduction member, railroad vehicle brake disk unit, railroad vehicle disk brake, railroad vehicle wheel, and railroad vehicle

An aerodynamic noise reduction member to be provided between a railroad vehicle brake disk and a disk-shaped rotating member rotated integrally with an axle of a railroad vehicle, the railroad vehicle brake disk including:

• an annular plate-like portion that has a sliding surface on a first side in a thickness direction;
• and a plurality of fins protruding from the plate-like portion toward a second side in the thickness direction, the plurality of fins being provided in a spaced apart manner in a circumferential direction of the plate-like portion, the aerodynamic noise reduction member comprising:
• a plate-like support portion to be sandwiched between the plurality of fins and the rotating member;
• and
• a plurality of protruding portions protruding from the support portion in a thickness direction of the support portion,
• wherein in a state in which the support portion is sandwiched between the plurality of fins and the rotating member, each of the plurality of protruding portions partially occludes between adjacent ones of the fins in the circumferential direction.