Časovno spremenljiv kontaktni razvoj v dinamiki sistema togih teles : doktorsko delo

slovenian

doktorska dela

2018

Univerza v Ljubljani, Fakulteta za strojništvo

The research presents an approach to solving multibody systems dynamics of rigid and flexible bodies using the method of absolute nodal coordinates formulation and by including the detection of several simultaneous contact situations. This work experimentally researches the rotational speed, electric current and the temperature dependent material properties of copper-graphite brush. The effect of brush temperature on material properties was analised by brush dynamics through measured damping ratio. Experimentally defined brush material properties were implemented in the dynamic model of the brush, brush holder and slip ring. The dynamic model confirmed the time variability of contact situations, which was detected in the measurements of contact resistance. Experimentally, was found that, due to the change in the material properties of the brushes in a narrow temperature range between 80°C and 90°C, the damping ratio increased by 15% and the wear rate increased up to a five-fold.

26.09.2023