Abstract:In this paper, a thermo-mechanical coupling analysis model of the spindle-bearing system based on Hertz's contact theory and a point contact non-Newtonian thermal elastohydrodynamic lubrication (EHL) theory are developed. In this model, the effect of preload, centrifugal force, the gyroscopic moment, and the lubrication state of the spindle-bearing system are considered. According to the heat transfer theory, the mathematical model for the temperature field of the spindle system is developed and the effect of the spindle cooling system on the spindle temperature distribution is analyzed. The theoretical simulations and the experimental results indicate that the bearing preload has great effect on the frictional heat generation; the cooling fluid has great effect on the heat balance of the spindle system. If a steady-state heat balance between the friction heat generation and the cooling system cannot be reached, thermally-induced preload will lead to a further increase of the frictional heat generation and then cause the thermal failure of the spindle.
In this article, an integrated thermal model is numerically analyzed to calculate the heat generation of spindle bearings and temperature distribution of the spindle system, with consideration of the operating conditions and lubrication conditions, such as rotation speed, preload, and oil film thickness. Surface roughness is an important parameter of elastohydrodynamic lubrication, which is measured by an optical topographer and characterized by statistical parameters. The experimental measurement system of the precision spindle is composed of a set of laser triangulation sensors and thermal infrared imagers. After the thermal characteristics, mathematical models are experimentally verified, and the effects of cooling oil temperature, cooling oil flow rate, and characteristic dimensions of the cooling channel on keeping the spindle gradient are analyzed in detail. The results indicated that temperature gradient across the spindle system can be significantly controlled by optimizing the technical parameters of the oil-cooling system.
Using VB 6.0 and CATIA software, this paper illustrates a method to generate the parameters and three dimensional shapes of the hydraulic torque converter blade automatically, in order to cut the development cycle. Finally, as an example of this methodology, a particular parametric design of a hydraulic torque converter blade is presented to verify the validity of the method by establishing a VB 6.0 program, which can generate the blade parameters and the three dimensional shape of the specific hydraulic torque converter blade.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.