[SY-O1] Thermodynamics of sliding contact: Joule-Thomson effect
The structure and properties (physical, thermal, mechanical, etc.) of complex materials during its formation process have strong correlation with the surrounding medium. Each of the material particles interacts with surroundings randomly, independently of each other, resulting from a probabilistic nature. This fact leads to the rich material properties with small changes in parameters.
An electrical contact pair in the commutator and brush assembly of the electric machine is of interest from the point of view of its structure due to material multivariance (carbon, metal, nanostructure, and others), which have a correlation with environment formed by wear particles or lubricant under sliding interaction. These elements exemplify the strong correlations between mechanical fluctuations of the wear particles and temperature behavior of the contact area (air with wear particles or lubricant), in particular, the non-equilibrium thermodynamics. In our paper we consider the abundance of wear particles as the porous plug. To study this throttling process, we shall concern with the stream as a two-phase system, in particular, gas medium and wear particles in the sliding contact. After due calculation, we receive the expression showing that measure of the strength of association between Joule-Thompson effect and the surrounding medium following a parabolic law, likewise under a temperature gradient, the temperature in contact area is not constant, it varies linearly with the coordinate of the entry end of the contact area. Furthermore, we consider two cases: kc = 1 and kc = 0.2. The comparison indicated a maximum difference of 30 percent of the thermal effects between the entry and outlet ends of the contact area. This means that the strong correlations that are responsible for mechanical fluctuation leads to the increase in the dispersion of the temperature fluctuations in the outlet end of the contact area caused by the corresponding susceptibility to the surrounding medium. The Joule-Thompson effect is probably one of the most important factors determining the different interaction conditions and accordingly material properties of the entry and outlet ends of the contact area between commutator and brush.
An electrical contact pair in the commutator and brush assembly of the electric machine is of interest from the point of view of its structure due to material multivariance (carbon, metal, nanostructure, and others), which have a correlation with environment formed by wear particles or lubricant under sliding interaction. These elements exemplify the strong correlations between mechanical fluctuations of the wear particles and temperature behavior of the contact area (air with wear particles or lubricant), in particular, the non-equilibrium thermodynamics. In our paper we consider the abundance of wear particles as the porous plug. To study this throttling process, we shall concern with the stream as a two-phase system, in particular, gas medium and wear particles in the sliding contact. After due calculation, we receive the expression showing that measure of the strength of association between Joule-Thompson effect and the surrounding medium following a parabolic law, likewise under a temperature gradient, the temperature in contact area is not constant, it varies linearly with the coordinate of the entry end of the contact area. Furthermore, we consider two cases: kc = 1 and kc = 0.2. The comparison indicated a maximum difference of 30 percent of the thermal effects between the entry and outlet ends of the contact area. This means that the strong correlations that are responsible for mechanical fluctuation leads to the increase in the dispersion of the temperature fluctuations in the outlet end of the contact area caused by the corresponding susceptibility to the surrounding medium. The Joule-Thompson effect is probably one of the most important factors determining the different interaction conditions and accordingly material properties of the entry and outlet ends of the contact area between commutator and brush.