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The journal bearings subjected to heavy load and slow speed operate in mixed lubrication regime causing contact between the interacting surfaces and resulting in wear. Complexity of wear behavior and lack of unifying theory/model make wear-control very challenging.

In the present research work, theoretical and experimental investigations have been conducted to explore the effect of grooving arrangements on the wear behavior of journal bearing operating in mixed lubrication regime. The theoretical model of Hirani (2005) that uses mass conserving cavitation algorithm has been used to determine the bearing eccentricity for different groove arrangements (with varying groove location and extent) for identifying a groove arrangement that minimizes the wear. The wear tests on the grooved bearings were conducted after suitable running-in of the new bearings on a fully automated journal bearing test set-up. A load and speed combination required to operate the bearing in mixed lubrication was used. The performance of different arrangement of bearing was evaluated by measuring their weight loss after the test.

Wear was significantly reduced with the use of proper groove arrangement for a bearing operating in mixed lubrication regime.

The improvement in bearing performance by providing grooves has been the subject matter of several studies in the past, but these studies were confined to the hydrodynamic operative regime of the bearing. In the present work, seven different combinations of axial and radial groove arrangement were tried, which has not been reported in any other work.

This paper aims to investigate the effect of misalignment on wear of spur gears and on oil degradation using online sensors.

The misalignment effect on gears is created through a self-alignment bearing, and is measured using laser alignment system. Several online sensors such as Fe-concentration sensor, moisture sensor, oil condition sensor, oil temperature sensor and metallic particle sensor are installed in the gear test rig to monitor lubricant quality and wear debris in real time to assess gearbox failure.

Offset and angular misalignments are detected in both vertical and horizontal planes. The failure of misaligned gear is observed at both the ends and on both the surfaces of the gear teeth. Larger-size ferrous and non-ferrous particles are traced by metallic particle sensor due to gear and seal wear caused by misalignment. Scanning electron microscope (SEM) images examine chuck, spherical and flat platelet particles, and confirm the presence of fatigue (pitting) and adhesion (scuffing) wear mechanism. Energy-dispersive X-ray spectroscopy analysis of SEM particles traces carbon (C) and iron (Fe) elements due to gear failure.

Gear misalignment is one of the major causes of gearbox failure and the lubricant analysis is as important as wear debris analysis. A reliable online gearbox condition monitoring system is developed by integrating wear and oil analyses for misaligned spur gear pair in contact.

This study aims to design an ideal magnetorheological (MR) brake that exerts negligible frictional torque in the off-state condition and controllable frictional torque in the on-state condition.

Silicone-based MR fluid, containing 9 per cent volume carbonyl iron particles, has been synthesized and used. The synthesized MR fluid is advantageous in maintaining low friction losses in off-state conditions. A magneto-rheometer has been utilized to characterize the off-state viscosity of the MR fluid at variable shear rates and shear stress of MR fluids at various magnetic fields. A mechanism to enhance the braking torque in the on-state condition has been designed and developed. An experimental test rig has been developed to capture the torque characteristics of the developed MR brakes. Three different designs of MR discs have been experimented under a magnetic field varying from 0 to 375 kA/m. Experimental results of braking torque under shear and compression modes have been presented.

Slotted disc MR brake gives much better torque performance.

The braking torque results motivate to use the slotted disc MR brake for high torque application.

The purpose of this paper is to report on the development of magnetorheological (MR) fluids, having high on-state shear stress/viscosity, low off-state shear stress/viscosity, good redispersibility and stable suspension of carbonyl iron particles, using tetramethyl ammonium hydroxide (TAH) and oleic acid.

MR fluids for use in brakes are synthesized using different weight percentages of silicone oil, TAH, oleic acid and iron particles. The effects of TAH and oleic acid are studied. Shear stress is measured as a function of magnetic field on a magneto-rheometer. The images of MR particles settling with time are presented. The test set-up used to evaluate the performance of the MR fluids synthesized for brake application is detailed. Finally, a significant improvement in the MR performance of brakes is reported.

The MR fluid having 0.25 Wt.% oleic acid showed low off-state viscosity/shear stress and high on-state viscosity/shear stress. A higher weight percentage of TAH in the MR fluid further reduced the low off-shear stress and increased the high on-state shear stress with better stability.

Improvement of MR brake performance by adding surfactants like TAH and oleic acid has been the subject matter of several studies in the past, but these studies used a fixed percentage of surfactants in MR fluids. In the present work, the optimum percentage of TAH and oleic acid for an improved braking performance is determined by varying their content in the MR fluid, which has not been reported in any other work thus far.

Rivers are very close to Indian culture and civilisation. Indians treat rivers as holy and connect them to their faith. Human-induced activities unintentionally pollute the water bodies. The present case revolves around an innovative social enterprise – PHOOL, which deals with the recycling of flowers offered by devotees at temples. Thus, preventing thousands of kilograms of floral waste from being dumped into rivers daily and polluting them. The idea was conceived to save the most revered river – the Ganges. These flowers are mostly loaded with pesticides and insecticides, which further merge with river water making it even more toxic, endangering marine lives. PHOOL collects flowers from various places of worship and recycles them into handcrafted incense sticks and biodegradable Styrofoam. This unique venture has also been patented for its process and technology of floral waste recycling. Their mission is to save and preserve the river Ganges and empower marginalised women by providing employment opportunities while at the same time giving a livelihood and a future to Indian child and the generations to come. The child could now afford schooling, in hopes of a better economic future in a healthier environment while maintaining all societal traditions. It is essentially a case of social entrepreneurship that aims to help readers understand the intricacies of starting and surviving a social enterprise and ensuring continual sustainability. To create the case, an interview was carried out with Ms Ekta Jain (Associate, Marketing and Communications, PHOOL), as well as a literature review and data were collected on the social enterprise and significant events that take place in the Indian social entrepreneurship ecosystem. PHOOL is a case on ensuring a balanced approach between the economy, environment and society. It aims at protecting and creating a balance between the environment, the economy and the society, generating a new inflow to the economy, providing a purpose in life for those most in need of it and a livelihood free from pollution and deprivation, and making the world a better place to live in. It is creating a balance between societal needs, the environment that requires protection, the economy and ensuring continuity.