Identification of thermal conductivity between external air and the case of the equivalent heat scheme of substitution of the asynchronous traction engine of a traw wagon

Abstract

The article is devoted to the method of determining the thermal conductivity between the external air and the equivalent thermal circuit for the replacement of an asynchronous traction motor with IP 54 protection level, which is used on tram cars. The specific features of the technique is the determination of conductivity, taking into account the thermal resistances between the following surfaces: the outer surface of the drooping part of the frame on the drive side and the outside air; The outer surface of the bed above the bag and the outside air, the outer surface of the hanging part of the frame on the fan side and the outside air, the outer surface of the bearing shield on the drive side and the outside air, and between the outer surface of the bearing shield on the fan side and the outside air.

According to the proposed method, the thermal conductivities between the external air and the hull for the asynchronous traction engine of the tram car AD 931 were determined with parameters with different engine speeds. It was shown that the thermal conductivity between the external air and the body increases from 6.13 W / K at 10 rpm to 93.5 W / K at 4400 rpm, which significantly affects the thermal conditions of the engine.