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In this work, a profile modification technique was used in design of a spur gear. In this technique, the tooth-sum is varied to obtain the desired contact ratio and low contact stress for a specified center distance. A program has been developed using C language to compute the contact stresses by varying the amount of profile shift for a tooth-sum of 100 teeth ( §4%). The selected tooth-sum of 96, 100, and 104 gears was subjected to cyclic loading using a back-to-back test rig. The morphology of the damaged gear tooth surface after cyclic loading was examined by scanning electron microscopy. The morphological investigation reveals that the degree of damage observed in negative number of teeth alterations is less compared to standard and positive alteration tooth-sum due to lower contact stress.

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This study presents a steady state and transient solution for a finite width two-lobe bearing operating with a non-Newtonian lubricant, obeying the power law model. A non-linear time-transient analysis is carried out and the orbital stability of journal is ensured by solving the equation of motion by fourth order Runge-Kutta method. Using the expressions for eccentricity ratio of lower and upper lobes and film thickness for each lobe, the modified Reynolds equation is solved separately for each lobe by finite difference technique with a successive over-relaxation scheme. Performance parameters of two-lobe bearing like load carrying capacity, Sommerfeld number, attitude angle; flow and friction parameter are determined and compared with the established results for Newtonian lubricants. Stability parameters are compared with circular bearings. It is found that the non-Newtonian effects are very prominent in the determination of load capacity, flow and friction characteristics of two-lobe bearings. Stability parameters of two-lobe bearings are considerably higher for all eccentricity ratios compared to circular bearings; hence these bearings are better suited for applications where whirl instability limits the speed at which the bearing can be operated.

The purpose of this paper is to study the effect of non-Newtonian lubricant on the stability of oil film journal bearings mounted on flexible support using linear perturbation technique. The model of non-Newtonian lubricant developed by Dien and Elrod is taken into consideration. The dynamic co-coefficients are calculated for different values of power law index and length to diameter ratio. These are then used to find stability margin for different support parameters to study the effect of the non-Newtonian lubricant.

The effects of sliding velocity in a spur gear for a tooth sum of 100 (altered by ±4%) with constant centre distance have been studied. The product of contact stress and sliding velocity (σ Vs) factor is calculated for varied profile shift. The effect of Hertzian compression, bending and shear deflection on sliding velocity at points along length of the path of contact has been computed. The scanning electron micrographs at pitch point C show that negative alteration in tooth‐sum gears is better compared with standard and positive alterations in tooth sum. Copyright © 2016 John Wiley & Sons, Ltd.

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<p class="apa">Maximum number of privately funded engineering institutions have been established in India in the last two decades to meet the growing needs of technical manpower required by the Engineering and IT companies as well as aspiring students after completion of the Pre-University Program. However, a large number of institutions have not been able to attract the talented students for their undergraduate programs. The private managements of those institutions have realized then, the need for maintaining high quality in imparting engineering education. In addition, the regulatory bodies like NBA insist on maintaining the quality in the educational programs before giving accreditation. Therefore, the young institutes need to know the best practices adopted by the high performing institutions and introduce those best practices in their programs. In this paper, an attempt has been made to identify the best practices of the reputed and ranking institutes, to classify and codify those practices so as to enable the young institutes to implement them. Quality indicators have been identified through literature review, by summarizing previous studies, by conducting discussion with experts in the field. A few top ranked engineering institutions are selected to identify and list the best practices, by referring to the finding of various magazines. Practices followed with respect to the quality indicators identified have been composed by conducting structured interviews and discussions with various core groups &amp; stake holders of these institutions. The details of literature review, data collection &amp; analysis, findings and policy implications of the research work are presented in this paper. The best practices enlisted through this study will act as guidelines to implement the quality initiatives for the young institutions.</p>