Research on the instantaneous temperature rise prediction of continuous electromagnetic launch guide rail based on data-driven technology

Abstract The presented work describes a computational method for carrying out a detailed and thorough examination of the flash temperature rise (i.e. the local ‘instantaneous’ temperature increase on a contact interface, due to frictional effects) present on the tooth flanks of a polymer gear pair, composed of a combination of POM and PA66 thermoplastics, during a given meshing cycle. The method involves a decoupled sequential procedure, where first the mechanical response of the gear teeth during a whole meshing cycle is analyzed using finite element analysis and, subsequently, a semi-analytical thermal analysis procedure is employed, with which the local flash temperature rise under a given tooth-pair contact can be evaluated. The method provides an accurate reproduction of the actual thermo-mechanical processes taking place at the gear teeth contact interfaces and allows for an investigation of the influence of deviations in the gear flank geometry and gear tolerances, while retaining a manageable enough form for application with moderate computational resources.

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Theoretical Analysis of the Effects of Instantaneous Charge Leakage on Roller Tracks of Roller Bearings Lubricated With High Resistivity Lubricants Under the Influence of Electric Current

Journal of Tribology ◽

10.1115/1.2920228 ◽

1990 ◽

Vol 112 (1) ◽

pp. 37-43 ◽

Cited By ~ 25

Author(s):

Har Prashad

Keyword(s):

Electric Current ◽

Contact Zone ◽

Temperature Rise ◽

Roller Bearing ◽

Rolling Friction ◽

Contact Stresses ◽

High Resistivity ◽

Roller Bearings ◽

Instantaneous Temperature ◽

Number Of Cycles

An analysis is presented for determining the effects of instantaneous charge leakage on the rise of contact temperature between rollers and roller track of races of roller bearings lubricated with high resistivity lubricant. Analysis is also given for the contact stresses on the races which lead to initiation of craters by the arcing effect on the roller tracks and subsequent damage to the roller bearing. Estimates of the leakage of charge between roller tracks and rollers during momentary asperity contacts along with an expression for the instantaneous contact resistance between roller and race was used to establish heat generated and instantaneous temperature rise in the contact zone on the roller tracks in each shaft revolution. Using this temperature rise, the contact stresses were determined and the minimum number of cycles was calculated before craters are initiated on the roller track of the races. The number of cycles thus determined corresponds, within the reasonable limits, to the appearance of the craters on the roller track of the inner race of a roller bearing, operated under the influence of electric current. Subsequently, the ratio of reduction in bearing life with that of the bearing operated under rolling friction without the influence of electric current is established. This paper gives general guidance for determination of instantaneous temperature rise due to charge leakage in the contact zone and makes it possible to predict the life of a roller bearing lubricated with high resistivity lubricant under the influence of electric current before the craters appear on the roller tracks.

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Transient temperature field analysis of variable viscosity RTHSB with a special structural cavity

Advances in Mechanical Engineering ◽

10.1177/1687814020965051 ◽

2020 ◽

Vol 12 (10) ◽

pp. 168781402096505

Author(s):

Jiafu Ruan ◽

Xigui Wang ◽

ShuE Ji ◽

Yongmei Wang ◽

Siyuan An

Keyword(s):

Temperature Field ◽

Film Thickness ◽

Dynamic Simulation ◽

Temperature Rise ◽

Variable Viscosity ◽

Operating Conditions ◽

Lubricating Oil ◽

Transient Temperature ◽

Oil Film ◽

Instantaneous Temperature

A radial thrust hydrodynamic sliding bearing (RTHSB) with special shaped cavity had been designed. Taking the instantaneous temperature rise characteristics of RTHSB as an analysis object, considering the influence of inlet lubricating oil velocity and transmission shaft speed, a dynamic simulation method of variable viscosity temperature field is proposed, and the mathematical model of instantaneous temperature rise of time-varying oil film is constructed. The correlation equation between instantaneous temperature rise and oil film variable viscosity is analyzed, the lubricating performance of a special-shaped cavity with variable thickness of the oil film considering real-time full operating conditions is revealed, and the alternating transient laws of oil film thickness with variable viscosity and its instantaneous temperature rise for no-load, heavy-load, and different rotating speeds are studied. It is obtained that the higher temperature area of profiled shaped cavity on reverse flow side extends to oil seal side with increase of rotating speed. The dynamic simulation of variable viscosity of RTHSB with different film thickness is simulated by using FLUENT software and the trend of transient film temperature field distribution of in special-shaped cavity is evaluated. The rationality of the mechanism analysis and numerical simulation results in this paper has been verified.

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