A rail vehicle, particularly train part of a high-speed train, wherein - the rail vehicle comprises a railcar body (11, 13) with a floor, which defines the bottom of a railcar body's interior for the transport of passengers and/or freight, - below the floor there is a receiving space (301; 401) formed for accommodating vehicle equipment (15; 201, 202, 204, 205, 206, 207, 208; 411, 412, 413, 417) to be cooled, wherein the receiving space (301; 401) is bounded on all sides, exhibits at least one air inlet aperture (307; 424, 425, 426, 427) and at least one air outlet aperture (139; 311; 419, 420, 421) and is protected against the ingress of dirt, - the at least one air inlet aperture (307; 424, 425, 426, 427) opens a main air volume of the receiving space (301; 401), wherein the main air volume contains the major part of the air in the receiving space (301; 401) and thus forms a reservoir for cooling air, - at least one device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is arranged in the receiving space (301; 401) and at least one fan (309; 410, 415) is arranged, which during operation accelerates air from the main air volume with the result that air flows to the at least one device to be cooled, wherein in the receiving space a plurality of vehicle devices (410, 411, 412, 413, 415, 417) to be cooled is arranged and distributed in the longitudinal direction of the rail vehicle over a longitudinal section of the receiving space, characterized in that the main air volume extends at least over the longitudinal section and the main air volume is continuous in the longitudinal section, i.e. not divided into individual compartments that are separate from one another and sealed off from one another, and in a first area of the said longitudinal section that is situated closer to the front end of the rail vehicle oriented in the direction of travel, where at least one (410, 411) of the vehicle's devices (410, 411, 412, 413, 415, 417) to be cooled is located, in side walls of the receiving space there is no air inlet aperture present, however in a second area of the longitudinal section, which compared to the first area of the longitudinal section is farther from the front end of the rail vehicle oriented in the direction of travel, there are air inlet apertures (424 - 427) arranged in the side walls of the receiving space, which open the main air volume of the receiving space (301; 401) to the surroundings of the rail vehicle through which air can enter into the main air volume of the receiving space. - the rail vehicle comprises a railcar body (11, 13) with a floor, which defines the bottom of a railcar body's interior for the transport of passengers and/or freight, - below the floor there is a receiving space (301; 401) formed for accommodating vehicle equipment (15; 201, 202, 204, 205, 206, 207, 208; 411, 412, 413, 417) to be cooled, wherein the receiving space (301; 401) is bounded on all sides, exhibits at least one air inlet aperture (307; 424, 425, 426, 427) and at least one air outlet aperture (139; 311; 419, 420, 421) and is protected against the ingress of dirt, - the at least one air inlet aperture (307; 424, 425, 426, 427) opens a main air volume of the receiving space (301; 401), wherein the main air volume contains the major part of the air in the receiving space (301; 401) and thus forms a reservoir for cooling air, - at least one device (15; 204, 205, 207, 208; 411, 412, 413, 417) to be cooled is arranged in the receiving space (301; 401) and at least one fan (309; 410, 415) is arranged, which during operation accelerates air from the main air volume with the result that air flows to the at least one device to be cooled,