Експериментальне дослідження опору кочення коліс автомобіля на роликовому стенді

Abstract

The article considers the results of experimental studies of the rolling resistance of car wheels on a roller stand. Also, the dependence of the coefficient of total resistances during wheel rolling on the stand rollers on the speed was established. Monitoring and diagnosing the technical condition of the rolling stock of vehicles from the point of view of traffic safety is one of the most important problems. This control is especially important for systems whose technical condition affects traffic safety, first of all, brake systems, as well as the power unit in the traction test mode. Foreign and domestic experience testifies to the effectiveness of instrumental control. Its advantages lie in the reliability of the values of the checked parameters. The diagnostic equipment includes roller stands, on which you can check the braking and traction properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. The inertial test method allows you to reproduce real speed and thermal modes of operation. To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the stand rollers. Studies of wheel rolling on the stand rollers have been carried out by many authors since the 70s of the last century. However, all of these studies were conducted on old bias tires. Now, only radial tires are used on passenger cars, the rolling resistance of which on rollers has practically not been studied. Therefore, returning to the study of this issue is relevant. The rolling resistance of wheels on the rollers of the stand will significantly affect the nature of their interaction during long-term running tests (due to increased heating of contacting bodies, power losses, violation of similarity conditions, etc.). It was found that the value of the rolling resistance coefficient noticeably depends on the ratio of the radii of the roller and the wheel, as well as the contact load, that is, the radial force of pressing the wheel against the roller, and in addition, on the speed and duration of the mode. The obtained results of the experiment made it possible to improve the theory of the interaction of a car wheel with the rollers of an inertial diagnostic stand. Also, the results of the experiments can be extended to different types of tires and the ratio of the radii of the wheel and roller.