Faculty Publications
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Item Design of haul road lighting system. Part II: Design based on optimal cost considerations(2006) Karmakar, N.C.; Mangalpady, M.; Rao, Y.V.; Yaragatti, U.R.The proper selection of lighting installations is very important for the provision of cost-effective lighting systems without compromising light quality. In this study a computer program was developed to evolve a cost-effective lighting system for haul roads in surface mines. This program is beneficial in assessing the viability of various lighting installations in order to achieve cost-effective solutions. Using the program, illumination design was studied for an 800 m long stretch of haul road. Nine different types of light sources were considered at mounting heights of 12 m and 16 m. The study shows that at a 12 m mounting height, 100 W high-pressure sodium vapour (HPSV) lamps offer the most cost-effective design, followed by 250 W HPSV lamps. In the case of 16 m pole heights the annual lighting cost is minimum for 150 W HPSV lamps, followed by 250 W HPSV lamps. This work also shows that optimum design based on energy consumption need not be the same as design based on optimum cost considerations as cost parameters may vary widely with location.Item Designing cost-effective lighting system for surface mine projects(2006) Mangalpady, M.; Karmakar, N.C.; Rao, Y.V.The objective of lighting in mines is to provide good illumination, which improves the safe and efficient working environment. The artificial lighting is very much essential for the sustained production, to meet the ever-growing demand of the mineral industry. Haul roads within the pit are one of the critical areas in surface mines where lighting installations are not permanent due to regular movement of faces. Though the initial investment for the lighting is very less compared to total project cost, the annual cost is considerably high against the running cost of the project. The proper selection of lamps, reflectors, mountings etc., for particular type of work is very important for energy efficient lighting system, without compromising with the quality of light. A computer model has been developed to evolve a cost effective lighting system for surface mine projects. This model helps in assessing viability of various light sources, so as to achieve energy effective solutions. Properly designed lighting system can prove to be a very cost effective investment for the mine owner.Item Computer aided slope stability analysis(2006) Sastry, V.R.; Ram Chandar, K.; Santosh, M.Primary purpose of slope stability analysis in most of the engineering applications is to provide safe and economic design of slopes that prevent failure. The analysis technique chosen depends on both site conditions and potential mode of failure which depends upon the rock mass characteristics. Various slope stability analysis techniques include physical, numerical and analytical methods. Physical modeling is a time consuming process and a costly affair, while analytical method involves past experiences, it is site specific and depends upon various parameters which are difficult to quantify. Numerical analysis with sophisticated softwares provides an accurate solution within short duration. This paper presents an in-house developed software package called "V-slope" to analyze and interpret the slope with options for suggesting suitable safety measures based on the nature of slope. Slip circle and tension crack techniques were considered for analysis. The slope profile for different factor of safety (FOS) values will be displayed on the screen for easy understanding. In case the FOS is lower than the required, the V-slope gives suggestive measures. In case of temporary slopes the only way by which slope failure can be prevented is by decreasing the slope angle and in such cases the program gives additional volume of material to be excavated and the likely additional cost incurred for various slope angle options. For permanent slopes, option is provided for designing the soil nails, i.e. number of bolts required, length, diameter and spacing of the bolts etc. Finally the V-slope is compared with a comprehensive commercial software package Slide and the results were found very much satisfactory.Item Hydrodynamics characterization of a counter-current spray column for particulate scrubbing from flue gases(2008) Biswas, S.; Rajmohan, B.; Meikap, B.C.Growing environmental concern and tightening of the regulations for particulate emission from various sources force us to think of an alternative technology for their control, which is cost effective and of high performance. A spray column using a wet process to control the particulates offers design simplicity, and has various other advantages over other conventional equipment used in industry. This work presents the hydrodynamic study of the spray column for the removal of particulates from gaseous wastes. Experiments were carried out to quantify pressure drop (?P), for varied gas and liquid rates ranging from 3.084 × 10-3 to 5.584 × 10-3 Nm3/s and 8.35 × 10-6 to 33.34 × 10 -6 m3/s, respectively with QL/QG ratio ranging from 1.59 to 10.81 m3 per 1000 ACM (actual cubic meter). The maximum pressure drop incurred in the column is 327 N/m3, which is at a gas rate of 5.584 × 10-3 Nm3/s, liquid rate of 33.34 × 10-6 m3/s, and an inlet solid loading range of 0-2.5 kg/m3. This is quite low compared to other wet process-based equipment, thus making it a low power loss scrubber. These results have further demonstrated the impact of solid dust (particulates) on the pressuredrop-hydrodynamics. A correlation was put forward for prediction of the overall pressure drop in the column. The experimental values agreed well with the predicted values, with minimum percentage error and standard deviation. © 2008 Curtin University of Technology and John Wiley & Sons, Ltd.Item The alternative building materials and technologies for individual housing in coastal Karnataka, India(CAFET INNOVA Technical Society 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2011) Rao, R.K.; Shetty, S.K.; Souza, J.K.D.The various research organizations in the country and world wide are in continuous investigation to develop different alternative materials and technologies. In the development of alternative materials, it is always emphasized to use locally available materials like mud, fibre, powder, stone etc. or a mixture of them to produce a different product to be used in modern day construction. This paper likes to give an insight into the various types of technologies developed by these Organizations and implemented right from the basic materials like building blocks to finished roofing elements in coastal Karnataka, India. It also discusses how these techniques are implemented and put to use for the benefit of the common man. It also enlightens the cost effectiveness and the energy efficiency that could be achieved in using these alternative materials and technologies in the region. © 2011 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Sustainable approaches for utilizing waste in building construction: Two case studies in India(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Kasthurba, A.K.; Reddy, K.R.; Venkat Reddy, D.V.Problems associated with increasing waste due to rising urban developments and its environmental concerns are reviewed. The challenges and standards for sustainable construction are outlined. This study explores potential utilization of different types of waste materials in building construction for its efficient and sustainable management. The benefits and challenges in utilization of waste for building applications are reviewed. Two case studies which demonstrate effective utilization of waste in construction projects carried out in India are outlined. These sustainable approaches of managing waste in building construction shall help private and governmental agencies to incorporate effective waste management strategies in future. This study will offer a background and useful guide for engineers and material scientists to develop standards and specifications for cost effective alternate building materials and techniques for economy, energy, and environmental benefits. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Use of Laterite as a sustainable building material in developing countries(CAFET INNOVA Technical Society cafetinnova@gmail.com 1-2-18/103, Mohini Mansion, Gagan Mahal Road, Domalguda, Hyderabad 500029, 2014) Kasthurba, A.K.; Reddy, K.R.; Venkat Reddy, D.V.Utilisation of local materials is an important step to sustainable construction to reduce transportation cost, save embodied energy, and protect the environment. This paper advocates the use of local laterite-a soil type rich in iron and alumina formed under hot and wet tropical conditions-due to its cost effectiveness and energy efficiency than that of conventional modern materials in tropical developing countries. This paper summarizes the occurrence and characteristics of laterite and then highlights the need for developing universal database of properties and standard testing protocols to facilitate evaluation and extensive use laterite in building applications. Understanding of properties and potential challenges of using this material will benefit for the development of suitable strategies/techniques for sustainable construction. Overall, this study identifies various factors that should be considered for efficient utilization and managements of laterite in construction to meet the growing demand of new housing and infrastructural in different regions of developing tropical world. © 2014 CAFET-INNOVA TECHNICAL SOCIETY. All rights reserved.Item Simple glucose reduction route for one-step synthesis of copper nanofluids(Springer Nature, 2014) Shenoy, S.U.; Nityananda Shetty, A.One-step method has been employed in the synthesis of copper nanofluids. Copper nitrate is reduced by glucose in the presence of sodium lauryl sulfate. The synthesized particles are characterized by X-ray diffraction technique for the phase structure; electron diffraction X-ray analysis for chemical composition; transmission electron microscopy and field emission scanning electron microscopy for the morphology; Fourier-transform infrared spectroscopy and ultraviolet–visible spectroscopy for the analysis of ingredients of the solution. Thermal conductivity, sedimentation and rheological measurements have also been carried out. It is found that the reaction parameters have considerable effect on the size of the particle formed and rate of the reaction. The techniques confirm that the synthesized particles are copper. The reported method showed promising increase in the thermal conductivity of the base fluid and is found to be reliable, simple and cost-effective method for preparing heat transfer fluids with higher stability. © 2012, The Author(s).Item Novel Co-Ni-graphene composite electrodes for hydrogen production(Royal Society of Chemistry, 2015) Subramanya, B.; Ullal, Y.; Shenoy, S.U.; Bhat, D.; Hegde, A.C.Active, stable and cost-effective electrocatalysts are key to water splitting for hydrogen production through electrolysis. Herein, we report the facile preparation of highly porous Co-Ni-graphene (Co-Ni-G) composite electrodes by electrodeposition for electrocatalytic applications. The incorporation of graphene into the Co-Ni matrix enhances the catalyst's activity for the hydrogen evolution reaction (HER) in an alkaline solution. The best coating exhibits a maximum current density of -850 mA cm-2 at -1.6 V, which is approximately 4 times better than that of the binary Co-Ni alloy indicating higher activity for hydrogen production. The addition of graphene to an electrolyte bath results in a porous encapsulated bundle of alloy nano-particles within the graphene network which effectively increases the electrochemically active surface area. As indicated by XPS analysis results, on addition of graphene the Co(0) and Ni(0) content in the deposit increases and as a result both cobalt/cobalt oxide and nickel/nickel oxide sites are evenly distributed on the Co-Ni-G electrode surface which is responsible for increased HER activity. The Tafel slope analysis showed that the HER follows a Volmer-Tafel mechanism. The structure-property relationship of the Co-Ni-G composite coating has been discussed by interpreting field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analysis results. © The Royal Society of Chemistry 2015.