Closure to “Discussion of ‘An Experimental Investigation on the Temperature Distribution in Circular Journal Bearings’” (1986, ASME J. Tribol., 108, p. 626)

A model has been developed to compute the dynamic stiffness and damping properties of externally pressurized, porous-wall, gas journal bearings which includes the effects of journal rotation and eccentricity. This paper presents the derivation of the governing equations and the perturbation analysis used to find the unsteady characteristics. Typical nondimensional performance curves are found and the influences of seven governing parameters are discussed. A companion paper describes an experimental investigation of porous journal bearings.

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Peak Temperature Correlation and Temperature Distribution during Joining of AZ80A Mg Alloy by FSW – A Numerical and Experimental Investigation

Strojniški vestnik – Journal of Mechanical Engineering ◽

10.5545/sv-jme.2020.6566 ◽

2020 ◽

Vol 66 (6) ◽

pp. 395-407 ◽

Cited By ~ 1

Author(s):

p Sevvel ◽

S.D. Dhanesh Babu ◽

R. Senthil Kumar

Keyword(s):

Experimental Investigation ◽

Temperature Distribution ◽

Quadratic Equation ◽

Peak Temperature ◽

Mg Alloy ◽

Element Analysis ◽

Temperature Correlation ◽

Friction Stir ◽

Az80a Mg Alloy ◽

Experimental Values

A quadratic equation has been developed based on experimental measurements to estimate the peak temperature in the friction stir welding (FSW) process during the joining of AZ80A Mg alloys. The numerical simulation of the FSW process was performed by employing COMSOL software to predict and calculate the distribution of temperature on the various regions of the parent metal and the welded joints. The predicted and finite element analysis (FEA) simulating the results of the distribution of peak temperatures were found to be consistent with the experimental values. In addition to this, a parametric experimental investigation was conducted to identify the most influential process parameter that plays a significant role in the peak temperature distribution during FSW of AZ80A Mg alloy. Linear contributions by the input process parameters of FSW, namely, traversing speed, rotating tool speed and axial force on the peak temperature were observed to be 32.82 %, 41.65 % and 21.76 %, respectively.

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Study of Anisothermal Short Journal Bearings With non-Newtonian Lubricants

Journal of Applied Mechanics ◽

10.1115/1.3627316 ◽

1965 ◽

Vol 32 (4) ◽

pp. 781-787 ◽

Cited By ~ 18

Author(s):

R. I. Tanner

Keyword(s):

Temperature Distribution ◽

Friction Coefficient ◽

Approximate Method ◽

Journal Bearings ◽

Newtonian Fluids ◽

Small Viscosity ◽

Film Viscosity

The equations describing the flow of simple non-Newtonian oils in short journal bearings are solved approximately for low eccentricity ratios and small viscosity variations with temperature. An approximate method for predicting the temperature distribution is compared with available experiments and appears to give realistic results. It is also shown that the reduction in friction coefficient observed by Dubois, Ocvirk, and Wehe in experiments with non-Newtonian fluids cannot be explained by accounting for through-film viscosity variations.

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