Applied Mechanics and Materials Vols. 813-814

Abstract: Drain cleaning is often considered as a simple task, but it might not be so always. Many industries function smoothly by constantly dumping the waste, toxic chemicals, biodegradable products frequently in the drains, which results in clogging of drains thus preventing the water flow from the pipes. Around 800 men die because of drain cleaning every year in India. Maintaining, cleaning and resolving the issues of drainage systems have been a severe issue in the surrounding environment where, labors are used without any protective measures. Increase in the laborers deaths has been a major concern in cleaning the drainage blockages. Moreover, identifying the blockage within the drainage system is a time consuming and TDS task. Also, the machines available are very expensive. Thus, a system has to be introduced where humans are not insisted for cleaning the drainage blockages and its maintenance. In view of above, present project is aimed at development of a slender and powerful system to inspect the pipe and disintegrate it to clear the blockage in the pipe.

Abstract: Degradation of agriculture due to lower yield and lack of labour is an issue that needs to be looked upon and resolved. The solution comes through implementation of a well proven technique called “The System of Rice Intensification (SRI)”. The solution requires large amount of manpower and the task being very laborious involving working in stooping posture. The improvement involves incorporating the principles of SRI for better yield. This paper focusses on designing and developing an equipment for the implementation of SRI in the field at low cost.

Abstract: The work presented here is the study of combining two separate processes into single process by providing an automated pneumatic setup in ASHOK LEYLAND PVT LTD company. The process is carried out by using a fixture which could clamp the air seal in position. A pneumatic cylinder of suitable load is to be used on the rail arrangement to carry out oil sealing. The main objective of this work is to reduce the setup time and also to prevent the workers from getting injured while handling manually.

Abstract: With the fast depletion of the conventional energy resources and the amount of pollution it is creating, the entire world is looking for an alternative non-conventional and a renewable energy to lessen the dependency on the conventional energy resources. In this scenario, utilizing solar energy which is abundant in nature is gaining high attention. One way of utilizing solar energy is by using solar photovoltaic cells which convert light energy into electrical energy, but they are too costly and less efficient. Many techniques are being developed to reduce the cost and improve the efficiency in harnessing solar energy. Sun tracking technique is one of the methods to increase the efficiency of solar cells. The present work is focused on providing a microcontroller based automatic two-axis sun tracker using Photodiodes as sensors to track sun. The system is assisted with a manual control through LabVIEW (Graphical User friendly Interface) to aid during bad weather conditions.

Abstract: Determination of workspace is one of the main considerations in the design of any robot since the workspace geometry is considered a fundamental issue for robot design. This also plays a crucial role in trajectory planning. Among parallel manipulators, 6-DOF Stewart platforms is the most researched and widely used robot. However, till date there is no closed form expression of workspace volume for Stewart platform. In this paper, a novel method is proposed to find out the workspace volume of Stewart platform. In this paper, individual workspace of each leg of the manipulator (P-U-S) is determined and then translated by a common distance towards their geometrical center thus generating constant orientation workspace. To determine the workspace volume, geometric intersection of the six spheres is computed. This results in workspace of definite shape and size, whose volume is calculated using simple formulae. It is observed that the geometric way of determination of workspace area is computationally less tedious than the algebraic method. This also helps a lot for workspace optimization of such manipulators.

Abstract: Magneto-rheological fluids belong to a group of non-Newtonian fluids, and represent a group of purely-viscous fluids with the controllability of their properties by means of a magnetic field. In the present work, MR damper setup has designed and fabricated. MR fluid is prepared by mixing the lubricating oil, distilled water and iron particles of size 500 meshes in the standard proportions. During the experimentation, arrangement is made for load which falls on the piston head of MR damper to determine the damping effect. For every reputation, time and displacement of piston in the MR fluid is noted. Based on these parameters, velocity of the piston and rate of acceleration with respect to time and acceleration with respect to displacement is determined. Damping effect is calculated by using acceleration with respect to time and displacement respectively.

Abstract: Abstract. Foil bearings are self-acting hydrodynamics bearings used to support lightly loaded high speed rotating machinery. The advantages that they offer to process fluid lubricated machines usingworking fluid as a lubricant (ambient air) physically non-contacting high speed operation. Foil bearings have been considered as an alternative to conventional bearings with the capacity to cater for high-speeds and hostile environment (high temperature). However, the lack of load carrying capacity at relatively lower speeds limits their applications in heavy turbo machinery and as such are highly suitable in lightly loaded, high speed turbo machinery like small gas turbines.This paper discusses the design and assessment of dynamic characteristics in terms of load carrying capabilities as a function of speed, gap between the bearing and the runner as well as shape of foils for an air foil thrust bearing. The effects of various bearing parameters like foil thickness, number of foils fixed circumferentially and along the axis of rotation and with foil geometry configuration. Characteristics of performance defined essentially in terms of load carrying capabilities and static stiffness have been used for evaluation. Experiments were conducted both for angular foils (with inner edge height less than outer edge height) and square foils by varying number of foils. The experimental results shows that the effect of foil configuration enhances the load carrying capabilities of air foil thrust bearing.

Abstract: A gear plays a crucial role in the performance of a gear box. The faults in a gear reduces the gear life and if problem arises in shaft it affects bearing. Gear box is finally affected due to these faults. Vibration signals carries information about condition of a gear box which are captured using piezoelectric accelerometer. In this paper, features are extracted and classified using K nearest neighbours (KNN) algorithms for both time and frequency domain. The effectiveness of KNN in classification of gear faults for both time and frequency domain is discussed and compared.

Abstract: The study of bubble column reactors has its significance in applications such as multiphase reactors, aerators and in industrial waste-water treatment. Extensive works has been done in studying the hydrodynamics of a single gas bubble flowing through stationary liquid phase. The natural breakup of bubble during its motion has been studied in the past. In the Part I of the present work, hydrodynamics of an air bubble after its artificial splitting using a stainless steel mesh is experimentally studied using image processing and high speed photography. The significance of bubble splitting is that it increases the surface area of contact between stationery and moving fluid which in turn increases the rate of reaction desired during the process. The motion of the bubble is captured during its release and after splitting using High-Speed Camera. The velocity, area and diameter of the bubble before and after splitting are calculated by applying Image processing technique on the high speed photograph. The splitting of the bubble is found to vary with the superficial gaseous velocity. The splitting of bubbles into two bubbles of nearly equal size is considered and its hydrodynamic characteristics are studied.

Abstract: The present work deals with the use of CFD analysis and the validation of the experimental work carried out on the artificial splitting of an air bubble in a bubble column reactor. In Part I of this work, artificial splitting of bubble in a bubble column rector is experimentally studied by using a high speed camera. Image processing technique was used to identify bubble size and bubble velocity. In present work CFD simulations are carried out using ANSYS FLUENT software using Volume of Fluids (VOF) method. VOF is based on a surface tracking technique applied to a fixed Eulerian space. The phase fraction in physical quantities that can be used to distinguish the distribution of gas hold up in a bubble Column reactor. The numerical study of splitting of bubble into two bubbles of nearly equal size is considered. In the bubble column reactor, the liquid phase is stationary and gas flow rate in it is varied. The superficial gas flow rates are 10 lph, 15 lph, 20 lph and 25 lph. The characteristics of bubble after splitting which include its shape, size and velocity for various gas flow rates mentioned above are studied numerically and are compared with experimental results. These hydrodynamic characteristics play a pivotal role in the reactions occurring between the liquid and gas phases in the bubble column reactor.