Browsing by Author "Murthy, Ch.S.N."

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An experimental investigation of jack hammer drill noise with special emphasis on drilling in rocks of different compressive strengths
(2007) Vardhan, H.; Murthy, Ch.S.N.
An attempt has been made in this paper to investigate the influence on sound level due to drilling in rocks of varying physical properties i.e. compressive strength and abrasivity using jackhammer drill. For this purpose, a jackhammer drill setup was fabricated wherein the thrust applied can be varied while drilling vertical holes. The compressive strength and the abrasivity of various rock samples collected from the field were determined in the laboratory. A set of test conditions were defined for measurement of sound level of the jackhammer drill. Also, with the help of the experimental setup, vertical drilling was carried out on the rock samples for varying thrust and air pressure values and the corresponding A-weighted equivalent continuous sound levels were measured. The results of this study indicate that, increase in thrust increases the sound level at higher midband frequencies in the noise spectrum. The study indicated the sound level near the drill rod to be 0.5 to 1.5 dB, 2.0 to 3.0 dB and 4.0 to 6.0 dB higher relative to that at the drill bit, the exhaust and the operator's position respectively at an air pressure of 5 kg/cm2 and 160 N thrust for all the rock samples tested. Both the thrust and air pressure were found to have a significant effect on the sound level produced by jackhammer drill at all the measurement locations. The study further shows that an increase in sound level of the order of 1.5 to 2.5 dB at the operator's position can occur with an increase in air pressure by 2 kg/cm2 at 160 N thrust and with an increase in compressive strength and decrease in abrasivity of rocks. Also, the increase in sound level at the operator's position with increase in compressive strength and decrease in abrasivity of rock is of the order of 1.0 to 2.0 dB. In order to maintain a constant penetration rate in the rocks, both the thrust and air pressure need to be increased with an increase in compressive strength and decrease in rock abrasivity. Therefore, increased compressive strength and lower abrasivity of rocks will require higher air pressure and thrusts to be applied to achieve an optimum penetration rate and therefore will result in higher sound level at the operator's position and at other measurement locations. © 2007 Institute of Noise Control Engineering.
Applications of computer in mining industry with special regard to shovel-dumper productivity
(2007) Mangalpady, M.; Murthy, Ch.S.N.; Pai, R.; Nand, R.
Now-a-days computer is used in every field of engineering, including mining industry, at various stages in various capacities. One of the major problems in surface mining is material handling, which involves transportation of both ore and overburden. Most of the projects make use of shoveldumper system in spite of its huge capital investment and recurring costs. Hence a lot of mind and time has to be devoted before its procurement so as to optimize their number and maximize its utility. This paper addresses various optimization models available for productivity analysis of shovel-dumper fleet. Match factor method is one of the commonly used techniques to know the relative coverage which shovels are getting from truck fleet. Operations research techniques like queuing theory, integer programming, simulation and goal programming consider the probabilistic nature associated with the system. Even though many models are available for optimization and analyzing the productivity of shovel dumper system, further research and study is needed to devise a desirable technique for the same.
Bifacial Solar PV Systems: A Sustainable Solution for Energy-Intensive Industries
(Institute of Electrical and Electronics Engineers Inc., 2024) Bojja, S.K.; Kunar, B.M.; Murthy, Ch.S.N.
Energy-intensive industries and mineral-based industries demand a considerable quantity of power for numerous uses. This is a big challenge because these procedures need a continuous and constant energy source, which requires an uninterrupted power supply. In theory, industries complement, replace, or lessen the effects of using fossil fuels by utilizing renewable energy, carbon capture, and energy recovery. However, combining renewable energy sources, such as solar power, can significantly lower overall operating costs and carbon emissions to meet the energy needs of different industrial applications. This study describes the installation, for research purposes, of a prototype bifacial solar PV system (BSPV) equipped with a pumping motor. A BSPV system is being investigated because its output energy will be higher than that of monofacial solar cells. BSPV systems use less space than monofacial ones while still producing the same power and being less expensive as well. Â© 2024 IEEE.
Effect of thermal response on physical properties during drilling operations-A case study
(Elsevier Ltd, 2018) Vijay Kumar, S.; Murthy, Ch.S.N.; Kunar, B.M.
The temperature induced or generated during deep hole drilling operations is due to the heat generated between the interface of work piece surface and the tool surface. Several research study have been conducted to predict the temperature involved while drilling process as a predominant functions of many parameters like feed rate, torque, depth of cut etc. Similarly many experimental procedures have been conducted by several researchers to measure temperature directly by using thermocouples, infrared measurement, pyrometer, and thermisters etc. There is no precise experimental method is available to measure analytical value of energy, power, heat flux etc, while drilling process. The temperature rigma depends on material compositions and physical properties. This paper presents the influence of temperature on physical properties of some study samples during drilling operations. Â© 2017 Elsevier Ltd.
Experimental investigation on corrosion control of 13CR L80 steel in hydrochloric acid solution using thiophene methanol
(2014) Puthalath, P.; Surendranathan, A.O.; Murthy, Ch.S.N.; John Berchmans, L.
The influence of different eco-friendly inhibitors on the corrosion behavior of 13Cr L80 steel in 15% HCl solution was experimentally investigated. In the preliminary study, corrosion tests were performed with various oil well steels like13Cr L80, L80, N80 and P110 steels in order to evaluate the comparative corrosion resistance of these metals when exposed to 15% aqueous hydrochloric acid solutions without inhibitors. In this paper the inhibitive action of a selected inhibitor, thiophene methanol (TML) on the corrosion behaviour of 13Cr L80 steel in 15% HCl solution at different levels of concentrations (0-100 mM) was investigated using weight-loss, electrochemical polarization and AC impedance spectroscopic methods and their results were compared. The inhibition efficiency of TML increased almost linearly with its concentration and was found to be maximum (86.79%) at 75 mM and the increase in temperature resulted in the decrease of the inhibitor efficiency (?) and degree of surface coverage (?). Surface morphology of the corroded sample was analyzed by SEM. FT-IR spectral study and TGA were carried out to characterize the surface products. The result shows that TML is a good inhibitor for 13Cr L80 steel in HCl acid medium. The adsorption of the TML on the 13Cr L80 steel surface obeyed the Langmuir adsorption isotherm. Thermodynamic and activation parameters are discussed.
Experimental, simulation and a case study on electrical energy consumption in mine drive haulage system
(2015) Moger, G.D.; Murthy, Ch.S.N.; Yaragatti, Udaykumar R.
The experimental investigation study on energy consumption of fabricated 3hp mine drive haulage system is presented. The performance analysis of energy consumption based on existing mine drive haulage system of underground coal mine and experimental set-up is prepared in the laboratory for a 3-hp wound rotor induction motor. The experimental and a case study results are simulated using MATLAB /simulink model and the compared results are presented in this paper. � 2015 IEEE.
Influence of Structural Discontinuity on Slope Stability using Numerical Modelling and Sirovision
(Books and Journals Private Ltd., 2024) Raja, S.; Murthy, Ch.S.N.
The rock mass consists of heterogeneous and anisotropic materials, with smaller and larger blocks of rock, and the presence of structural discontinuities is a significant concern. Characterising the rock mass is crucial for the success of engineering excavations in such areas. A detailed study of joints, their orientation, and discontinuities in the exposed rock mass is crucial as they greatly influence stability and fragmentation. Existing rock mass classifications like Rock Mass Rating (RMR) and Q-classification require various geological parameters and physico-mechanical properties of the rock. However, determining these parameters conventionally can be time-consuming, requiring careful on-site measurements. The number of opencast coal mines is increasing compared to underground mines due to shorter gestation periods, higher productivity, and quicker returns. However, opencast mining raises environmental concerns such as air and water pollution, solid waste management, land degradation, and socio-economic issues. Additionally, many opencast coal mines, regardless of size, are reaching greater depths, making analysing bench slopes and ultimate pit slope design crucial. Slope failure in these mines leads to production loss, additional costs for recovery and handling of failed material, pit dewatering, sometimes mine abandonment or premature closure, and loss of life. A study was conducted at Prakash Khani Opencast Mine – IV, Manuguru area, M/s The Singereni Company Collieries Limited (SCCL), to investigate the influence of structural discontinuities on slope stability. SIROVISION software was used to assess rock mass characterisation, while PLAXIS-2D software was employed to analyse the influence of structural discontinuities on slope stability. A comparative conclusion was drawn based on the results obtained from SIROVISION and PLAXIS-2D analyses. The study revealed that the RMR of the mine ranged from very poor to fair due to numerous discontinuities. It was also found that discontinuities in the slope decrease the Factor of Safety (FOS), indicating an impact on slope stability. © 2024, Books and Journals Private Ltd.. All rights reserved.
Investigation of Noise Level and Penetration Rate of Pneumatic Drill vis-à-vis Rock Compressive Strength and Abrasivity
(Springer India sanjiv.goswami@springer.co.in, 2014) Kivade, S.B.; Murthy, Ch.S.N.; Vardhan, H.
In this paper, detailed studies were carried out to determine the influence of rock properties on the sound level produced during pneumatic drilling. Further, investigation was also carried out on the effect of thrust, air pressure and compressive strength on penetration rate and the sound level produced. For this purpose, a fabricated pneumatic drill set up available in the institute was used. Rock properties, like compressive strength and abrasivity, of various samples collected from the field were determined in the laboratory. Drilling experiments were carried out on ten different rock samples for varying thrust and air pressure values and the corresponding A-weighted equivalent continuous sound levels were measured. It was observed that, very low thrust results in low penetration rate. Even very high thrust does not produce high penetration rate at higher operating air pressures. With increase in thrust beyond the optimum level, the penetration rate starts decreasing and causes the drill bit to ‘stall’. Results of the study show that penetration rate and sound level increases with increase in the thrust level. After reaching the maximum, they start decreasing despite the increase of thrust. The main purpose of the study is to develop a general prediction model and to investigate the relationships between sound level produced during drilling and physical properties such as uniaxial compressive strength and abrasivity of sedimentary rocks. The results were evaluated using the multiple regression analysis taking into account the interaction effects of predictor variables. © 2014, The Institution of Engineers (India).
Investigation on dust generated during rock cutting by ansys software
(2015) Raghavan, V.; Murthy, Ch.S.N.; Sastry, V.R.
Underground coal mining operations continue to increase production as mining equipment and practices are improved. Unfortunately, increased production also results in the potential for increased Respirable dust generation and worker exposure. In response, operations are applying basic controls at elevated levels and looking to emerging technologies in an effort to better control Respirable dust levels. Ventilating air and water sprays remain the basis of dust control strategies for both longwall and continuous mining operations, and the level of application for these controls continued to increase. In addition, new technologies are emerging that have the potential to further reduce dust levels. In this Paper an attempt is made to study the Stresses Produced and its Influence on Dust generation at different Attack angle and force applied on the cutting material.
Investigation on rock thermal properties in Godavari Valley Coalfield, Telangana, India
(CRC Press/Balkema, 2024) Dileep, G.; Tripathi, A.K.; Murthy, Ch.S.N.; Ray, L.
The study of thermal properties provides significant contributions to the field of geothermal research, material characterization, geological assessments and optimization of heat load in underground mines. The research focuses on the examination of thermal properties in rocks, specifically sandstone, aiming to explore the correlation between thermal properties with density and porosity. The investigation on sandstone rocks within the Godavari coal basin coal mines employed a steady-state instrument to measure thermal properties. The rocks exhibit notable variations in thermal conductivity (ranging from 1.10-4.38 W/m.K) and thermal diffusivity (ranging from 0.63-1.96 J/kg.K), which are substantially influenced by changes in both porosity (ranging from 0.6-19%) and density (ranging from 2.13-2.68 g/cm3). The research findings indicate that in sandstone rocks, thermal conductivity and thermal diffusivity rise with increasing density and decline with porosity. In contrast, the specific heat capacity of rocks remains constant. Â© 2024 The Author(s).
Microseismic monitoring of longwall strata to provide real time instability indications to mine management at Rajendra coalmine in India
(2008) Sivakumar, C.; Srinivasan, C.; Murthy, Ch.S.N.; Rao, Y.V.
Rooffalls are the most common problems encountered during various stages of longwall mine operation resulting in loss of production and machinery. A real time microseismic monitoring system was installed at Rajendra underground coal mine and acquired rock fracturing information from different roof layers. These data were analysed and obtained stress concentration zones, which ultimately resulted in rooffalls. Based on the microseismic event release rate advanced strata instability information was provided to mine management through daily reports. This information has helped in carrying out effective and optimized blasting operations to distress the high stress zone. The microseismic data also helped in mapping real time fracture process to get the extent of fractures in roof strata. The significant and reliable precursor found was microseismic event release rate (ERR) for rooffalls. Daily reports were submitted to mine management regarding stress concentration zones and rockfall information, which were confirmed from underground observations. The details of the microseismic technique and its application to longwall mine problems are discussed in this paper. � 2008, ARMA, American Rock Mechanics Association.
Microseismic monitoring of longwall strata to provide real time instability indications to mine management at Rajendra coalmine in India
(2008) Sivakumar, C.; Srinivasan, C.; Murthy, Ch.S.N.; Rao, Y.V.
Rooffalls are the most common problems encountered during various stages of longwall mine operation resulting in loss of production and machinery. A real time microseismic monitoring system was installed at Rajendra underground coal mine and acquired rock fracturing information from different roof layers. These data were analysed and obtained stress concentration zones, which ultimately resulted in rooffalls. Based on the microseismic event release rate advanced strata instability information was provided to mine management through daily reports. This information has helped in carrying out effective and optimized blasting operations to distress the high stress zone. The microseismic data also helped in mapping real time fracture process to get the extent of fractures in roof strata. The significant and reliable precursor found was microseismic event release rate (ERR) for rooffalls. Daily reports were submitted to mine management regarding stress concentration zones and rockfall information, which were confirmed from underground observations. The details of the microseismic technique and its application to longwall mine problems are discussed in this paper. Â© 2008, ARMA, American Rock Mechanics Association.
Multiple seam mining: A critical review
(2006) Khare, S.; Rao, Y.V.; Murthy, Ch.S.N.; Vardhan, H.
Multiple seam mining implies simultaneous working of more than one seam. The major problem encountered in this type of mining are related to ground control. These ground control problems are mainly due to the pillar load transfer. The pillar load transfer mainly depends on the physical characteristics of the parting material between the seams and also its thickness. There are various parameters affecting the multiple seam working. Broadly these parameters are classified into two i.e. fixed parameters and mine design parameters.' Fixed parameters are seam thickness, depth of seam, parting thickness, physical characteristics of the parting, geology of the seam, etc. Mine design parameters are sequence of working of the seam, method of working, pillar size, type of supports used, etc. Most of the coal reserve in India is locked up in multi-seams. This paper discusses the various research work carried out in India as well as abroad, related to ground control problems associated with multi-seam mining.
Performance analysis of PV panel under varying surface temperature
(2018) Kumar, T.A.; Murthy, Ch.S.N.; Mangalpady, A.
The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1�C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1�C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/�C. � The Authors, published by EDP Sciences, 2018.
Performance analysis of PV panel under varying surface temperature
(EDP Sciences edps@edpsciences.com, 2018) Tripathi, T.A.; Murthy, Ch.S.N.; Mangalpady, M.
The surface temperature of PV panel has an adverse impact on its performance. The several electrical parameters of PV panel, such as open circuit voltage, short circuit current, power output and fill factor depends on the surface temperature of PV panel. In the present study, an experimental work was carried out to investigate the influence of PV panel surface temperature on its electrical parameters. The results obtained from this experimental study show a significant reduction in the performance of PV panel with an increase in panel surface temperature. A 5W PV panel experienced a 0.4% decrease in open circuit voltage for every 1Â°C increase in panel surface temperature. Similarly, there was 0.6% and 0.32% decrease in maximum power output and in fill factor, respectively, for every 1Â°C increase in panel surface temperature. On the other hand, the short circuit current increases with the increase in surface temperature at the rate of 0.09%/Â°C. Â© The Authors, published by EDP Sciences, 2018.
Prediction of specific energy using dominant frequency of acoustics produced during diamond core drilling operations
(2020) Kumar, Ch.V.; Murthy, Ch.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).
Protective performance of furfuryl alcohol on 13Cr L80 steel against corrosion in hydrochloric acid solution
(2014) Puthalath, P.; Surendranathan, A.O.; Murthy, Ch.S.N.
The search for efficient inhibitors to mitigate the corrosion of oil-well steels requires more experimental investigations of the performance of ecofriendly nontoxic organic inhibitors. With this objective, the inhibitive action of a selected inhibitor, furfuryl alcohol (FAL), on the corrosion resistance of 13Cr L80 steel in 15% HCl solution was investigated using weight-loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) techniques. The inhibition efficiency of furfuryl alcohol was found to increase almost linearly with concentration and reached about 96% at 90 mM but decreased with temperature. The adsorption of the inhibitor on 13Cr L80 steel in the acidic solution was found to accord with the Langmuir isotherm. Thermodynamic and activation parameters were also evaluated. Scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, and thermogravimetric analysis (TGA) were carried out to establish the inhibitive properties of FAL. The results from these tests confirmed that FAL is a potential inhibitor for 13Cr L80 steel in HCl acid medium. © 2013 American Chemical Society.
Real time microseismic monitoring to study geomechanics of underground structures
(2008) Sivakumar, C.; Srinivasan, C.; Willy, Y.A.; Murthy, Ch.S.N.
The study of Geomechanics of underground structures in real time requires capture of fracture information well in advance from structure failure to initiate remedial measures during development and after completion of structure. The advanced high dynamic range microseismic instrumentation with latest Computer methods/algorithms helped to investigate strata behaviour in real time. One such investigation was carried out at the Rajendra longwall underground coal mine, Madya Pradesh state India and addressed major concerns of the mines like roof falls, stability of workings, goaf caving process etc,. The results of this study demonstrated that microseismic monitoring is very useful in understanding the geomechanics of underground structures. Among the several seismic source parameters obtained, the reliable precursor found was the microseismic Event Release Rate (ERR) of micro fractures before failure, which is the most significant instability indicator of underground structure. Results from this work can be useful to other underground structures such as tunnels and LPG storage caverns.
Real time microseismic monitoring to study geomechanics of underground structures
(2008) Sivakumar, C.; Srinivasan, C.; Willy, Y.A.; Murthy, Ch.S.N.
The study of Geomechanics of underground structures in real time requires capture of fracture information well in advance from structure failure to initiate remedial measures during development and after completion of structure. The advanced high dynamic range microseismic instrumentation with latest Computer methods/algorithms helped to investigate strata behaviour in real time. One such investigation was carried out at the Rajendra longwall underground coal mine, Madya Pradesh state India and addressed major concerns of the mines like roof falls, stability of workings, goaf caving process etc,. The results of this study demonstrated that microseismic monitoring is very useful in understanding the geomechanics of underground structures. Among the several seismic source parameters obtained, the reliable precursor found was the microseismic Event Release Rate (ERR) of micro fractures before failure, which is the most significant instability indicator of underground structure. Results from this work can be useful to other underground structures such as tunnels and LPG storage caverns.