The Analysis of the Characteristics of Infinitely Short Journal Bearings Modified by Equivalent Viscosity
The characteristics of unlimited short journal bearing has been analyzed by using the equivalent viscosity correction model under thin film lubrication conditions. The interaction between the lubricant and the surface within a very small gap has been seriously considered. The changes of regular pattern of lubricant properties are comprehensive analyzed and researched. Unlimited short journal bearing is regarded as the research object. After researching, the varying regularity of its characteristics has been received. At the same time, the relationship between parameters and bearing performance has been established. The basis are provided for theoretical research and practical engineering calculations.
PROGRESS OF RESEARCH ON NANOTRIBOLOGY
With the development of nano science and technol- ogy,nanotribology has been a fundamental technology involved in super precise machine and micro electromechanical systems, which focus on the atom/molecule-scale friction,lubrication and wear properties of tribological interfaces.Since early 1990s, Chinese tribologists have devoted themselves into this field and made remarkable achievements.The main research progress on nanotribology from the State Key Laboratory of Tribology, Tsinghua University is summarized,including thin film lubrica- tion,confined liquid properties,ordered molecular film lubrica- tion,interface friction and stick-slip phenomena,magnetic head/disk nanotribology and the development of experimental instruments,etc.To serve as a valuable reference for future study is expected in nanotribology.
Flow and Compaction During the Vacuum Assisted Resin Transfer Molding Process
The flow of an epoxy resin and compaction behavior of carbon fiber preform during vacuum- assisted resin transfer molding (VARTM) infiltration was measured using an instrumented tool. Composite panels were fabricated by the VARTM process using SAERTEX(R)2 multi-axial non- crimp carbon fiber fabric and the A.T.A.R.D. SI-ZG-5A epoxy resin. Resin pressure and preform thickness variation was measured during infiltration. The effects of the resin on the compaction behavior of the preform were measured. The local preform compaction during the infiltration is a combination of wetting and spring-back deformations. Flow front position computed by the 3DINFIL model was compared with the experimental data.