Faculty Publications
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Item Rock Engineering Design: Properties and Applications of Sound Level(CRC Press, 2013) Vardhan, H.; Bayar, R.K.Being knowledgeable about rock properties is vital to being effective in the design of blasts in mines, quarries and other construction projects. Without proper knowledge, the energy released during blasting can be underutilized, harm the environment, and may escalate costs. Rock Engineering Design: Properties and Applications of Sound Level aids s. © 2014 by Taylor & Francis Group, LLC.Item Development of probabilistic simulation model for production optimization in open pit mines(Nova Science Publishers, Inc., 2011) Raj, M.G.; Vardhan, H.; Rao, Y.V.Large mechanized open pit operations can become more efficient and competitive without additional costs by improving the productivity of the existing machinery. This can be achieved by ensuring higher availability and utilization of the equipment The present paper deals with truck dispatch system using a variety of strategies to enhance the production capacity of a given set of equipment (shovels and trucks) by way of continuous dispatching of trucks. A discrete event probabilistic simulation program has been developed to demonstrate the production potential of an operating mine. It can accommodate any number of shovels and trucks of different capacities. The characteristic features of each truck and shovel can be individually specified to reflect the reality of actual working conditions. The model was tested on a hypothetical mine and a real case to verify the logic used in the program development. Subsequently, the model was implemented in two real mines to investigate the production potential. It was observed that substantial scope exists for productivity improvement when the mines were operating on a flexible mode. © 2012 by Nova Science Publishers, Inc. All rights reserved.Item Prediction of specific energy using dominant frequency of acoustics produced during diamond core drilling operations(American Institute of Physics Inc. subs@aip.org, 2020) Vijaya Kumar, Ch.V.; Murthy, C.S.N.; Vardhan, H.The diamond core drilling operation is very essential in the preliminary stage of mineral extraction in the mining industry. The energy required to remove a unit volume of the rock mass (specific energy) is discussed in the present investigation. Estimation of the specific energy is the essential key parameter for tunneling, excavation, and other allied industries. It helps in reducing the time-consuming and cost of the project. For that, the laboratory experimental work was carried out on a laterite rock using CNC drilling machine BMV45T20. Using a multiple regression analysis reasonable mathematical equation was established among specific energy and dominant frequencies through diamond rock core drilling operations. The established prediction model could be utilized at the preliminary stage of the excavation projects for estimation of the specific energy in tunneling, excavation and petroleum industries. © 2020 Author(s).Item Shortcomings of Vibrating Screen and Corrective Measures: A Review(Springer Nature, 2020) Shanmugam, B.K.; Vardhan, H.; Govinda Raj, M.; Kaza, M.; Sah, R.; Harish, H.Screening is a process of separating two or more materials of size ranging from fine to coarse of different shapes, particle sizes and densities. The conventional vibrating screen is widely used in mineral and mining industries for performing sizing operation. This paper will be on the review of the various shortcomings of the conventional vibrating screen. The review was carried out through literature survey and plant visit. The paper also involves the remedial measures to be taken to overcome the shortcomings of the conventional vibrating screen. Some of the corrective measures are reduction in number of components also reduces overall screen load, angular velocities, stress, wear or damages to the screen, screen replacement, downtime and overall cost of production. The circular vibrating motion provided to the screen will give larger amplitude and stroke length of the screen which increases screening efficiency. The overall outcome of remedial action will lead to improved screening efficiency. This paper also provides the idea for the optimization of the vibrating screen design which can reduce the power consumption, friction and also provide high screening output. © 2020, Springer Nature Switzerland AG.Item Investigation of iron ores based on the bond grindability test(American Institute of Physics Inc. subs@aip.org, 2020) Hanumanthappa, H.; Vardhan, H.; Raj, G.R.; Kaza, M.; Sah, R.; Sinha, A.; Shanmugam, B.K.Grinding is a process of reduction of lumps to powder depending on the requirement of particle size and particle shape. The present investigation involves the identify the physical properties of three different types of iron ores by using Bond ball mill. The result shows that the maximum Bond work index of 14 KWh/mt was obtained for 'A' type iron ore sample. The Bond work index for 'B' and 'C' type iron ore sample are of 11 and 10 KWh/mt. The variation of BWI of three iron ore sample may be varied during the geological formation of each iron ore sample. The output product of three iron ore sample composed of three different size fractions when ground in Bonds ball mill. Based on the BWI and output product size of three iron ore samples are classified as hard ore ('A' type iron ore sample), medium hard ore ('B' type iron ore sample) and soft ore ('C' type iron ore sample). The classification of different types of iron ore helps to run the plant scale ball mill by setting suitable operating parameters to the ball mill. © 2020 Author(s).Item The screening efficiency of linear vibrating screen-An experimental investigation(American Institute of Physics Inc. subs@aip.org, 2020) Shanmugam, B.K.; Vardhan, H.; Raj, G.R.; Kaza, M.; Sah, R.; Hanumanthappa, H.Screening is a process of continuous physical separation of two or more powdered material depending on the particle size and particle shape. The present investigation involves the study of screening efficiency obtained in the widely used plant scale linear vibrating screen. The present investigation also involves the recommendations for improving screening efficiency. The result shows that the linear vibrating screen has the maximum screening efficiency of 65.92% for first 10 minutes of screening and reduced up to 59.34% for 60 minutes of screening. The reduction in screening efficiency with respect to screening time is due to the screen blinding. The screening of powdered materials faces the problem of screen mesh blinding which reduces the screening efficiency. The present authors recommend utilizing the screen configuration of circular vibrating screen which can provide higher screening efficiency with reduced screen blinding. The utilization of circular vibrating screen will reduce the screen blinding and prevents the labor requirement for removing screen blinding thereby increasing the efficiency and the production rate of screening. © 2020 Author(s).Item Effect of injection pressure on output of a CI engine fuelled with raw Cardanol and kerosene blends(Elsevier Ltd, 2023) Ravindra, n.; Mangalpady, M.; Vardhan, H.This study was aimed towards the investigation of effect of injection pressure on the performance of a CI engine run with various blends of raw Cardanol and kerosene. Three different volumetric blends of kerosene and cardanol (i.e., BK40, BK30 and BK20) were tested in diesel engine at 180 bar, 200 bar and 220 bar injection pressure. The results of the study indicated that at increased injection pressure brake thermal efficiency (BTE) increased with reduction in brake specific fuel consumption, unburned hydrocarbon and smoke. The maximum thermal efficiency of 31.34% was observed for BK30 blend at 220 bar and it was 31.97% for diesel fuel. Hence, this study reveals that kerosene cardanol blend can be used as CI engine fuel with proper tuning of injection parameters. © © 2023 Elsevier Ltd. All rights reserved.Item Assessment of heavy earth-moving machinery noise vis-à-vis routine maintenance(2006) Vardhan, H.; Karmakar, N.C.; Rao, Y.V.Exposure to noise from various types of equipment/machinery has been identified as a critical health hazard for personnel working in the Indian mining industry. Heavy Earth Moving Machinery (HEMM) used in mines has been identified as a major source of noise, and several earlier investigators have proposed various types of retrofit measures on these machines to reduce noise. The present work was taken up with the objective of evaluating the noise generation characteristics of HEMM as influenced by periodic maintenance. Detailed noise measurements were carried out in a large open pit coal mine located in India. The effect of maintenance on noise production was assessed for ten dumpers and three dozers by measuring the A-weighted one-third-octave band sound pressure levels after the machines had been subjected to maintenance at the end of 300 hours, 500 hours, 750 hours and 1000 hours of use. Measurements were also carried out to assess the effect of maintaining specific HEMM systems noise characteristics at 1000 hours. Assessment of sound pressure levels at each periodic maintenance revealed major sound level reductions with 1000 hours maintenance. The data also identified the major noise generating systems in HEMM as air systems, exhaust systems, cooling systems and fuel systems. © 2006 Institute of Noise Control Engineering.Item Production optimisation using simulation models in mines: A critical review(Inderscience Publishers, 2009) Raj, M.G.; Vardhan, H.; Rao, Y.V.The mining industry is faced with the task of responding to increased demand for mineral resource products, decreasing ore grades, stringent quality requirements and strict environmental regulations in trying to meet the demands of the economy. This situation has necessitated the search for more scientific and technological innovations that enable profitable mining like simulation studies. In this paper, system simulation studies in underground and open-pit mines, shovel truck simulation have been discussed in detail. The study shows wide applicability of simulation studies in various operations in both underground and open-pit mines. Copyright © 2009, Inderscience Publishers.Item Noise problem and its control for heavy earth moving machinery deployed in opencast mines - A critical review(2006) Vardhan, H.; Rao, Y.V.; Karmakar, N.C.Worldwide, increasingly stringent regulations are coming into force, limiting the exposure of workers to industrial noise. Industrial noise and its consequences, is thus growing importance to employers, local and central government officials, trade unions, occupational hygienists and physicians and insurers. India is not an exception far this. The mining industry in India is facing serious problem of noise due to increasing demand of minerals for which large capacity machines are being deployed producing high noise levels. The present paper thoroughly reviews the noise problem and its control for heavy earth moving machinery's deployed in opencast mines both in India and worldwide. The various noise control approaches for heavy earth moving machinery's deployed in opencast mines are also discussed.