Faculty Publications
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Item An experimental investigation of the sound level produced by bulldozers with various maintenance schedules(Inderscience Publishers, 2008) Vardhan, H.; Raj, M.G.This study was made to understand and evaluate the effect of maintenance on noise production from bulldozers through experimental measurements of sound levels in a large open cast mine. Assessment of sound pressure levels at each periodic maintenance interval revealed that maximum sound level reduction was achieved at 1000 h maintenance schedule. For other periodic maintenance intervals, reduction in A-weighted sound pressure level was below 1.0 dB. The study revealed that primarily, the major noise-generating systems in Heavy Earth Moving Machinery (HEMM) are air, exhaust, cooling and fuel systems. However, maintenance of lubricant, transmission and hydraulic systems yielded no significant improvements in sound levels. Results also indicated sound level emissions from various systems to lie in different frequency ranges. © 2008, Inderscience Publishers.Item Experimental and theoretical investigations on the cyclic operation of TSA cycle for air dehumidification using packed beds of silica gel particles(Elsevier Ltd, 2013) Ramzy K, A.K.; Kadoli, R.; Ashok Babu, T.P.Dehumidification using desiccant beds provide a good alternative for the conventional vapor compression cooling system. Desiccant material in the desiccant dehumidification system should undergo both adsorption and desorption processes. In the present work, experimental tests have been carried out for thermal swing adsorption (TSA) cycle utilizing two packed beds of silica gel spherical particles. The pseudo gas side controlled (PGC) mathematical model has been presented for predicting the cycle performance. The mathematical model has been validated using the experimental results. The root mean square of errors ranges from 1.15% to 9.03% for the exit air humidity ratio and from 1.08% to 9.68% for exit air temperature. The dynamics of desiccant bed during the cyclic operation has been investigated numerically. In addition, it has been found from the parametric study that the cycle efficiency is maximum for a regeneration temperature of 90-95°C when the bed length varies from 50 to 300mm and for desiccant particle diameter ranging from 2 to 5mm. A sensible cooling for the process air before undergoing the dehumidification period is recommended for increasing the cycle efficiency and the dehumidification time which is an added advantage. © 2013 Elsevier Ltd.Item Miniaturization of automobile radiator by using zinc-water and zinc oxide-water nanofluids(Korean Society of Mechanical Engineers, 2015) Sonage, B.K.; Mohanan, P.High performing fluids for energy conservation and energy efficiency replace conventional heat transfer fluids. This study relates to the development of an alternative heat transfer fluid called as nanofluid. Nanofluid is a dispersion of solid nanoparticles in a base fluid having enhanced thermal properties compared to base fluid. Zinc and Zinc oxide, being eco-friendly and having easy nanoparticle production processes, are considered for the synthesis of nanofluids of different volume fractions. In this experimental study related to heat transfer, the preparation of Zinc-water (Zn-H2O) nanofluid involves the single step method, while the preparation of Zinc oxide-water (ZnO-H2O) uses the two-step method. Six nanofluids comprising of three Zn-H2O and three ZnO-H2O in different volume fractions are tried for this study. Conduct an experimental study to calculate the enhancement of heat transfer coefficient and pressure drop compared to water. Apply the performance evaluation criterion to assess the heat transfer performance of the considered nanofluids. Amongst the six nanofluids, Zn-H2O nanofluid of 0.5% volume fraction proves to have the best heat transfer performance. Then, assess this high performing fluid theoretically in an automobile radiator to get benefits of its use. If by replacing the water with Zn-H2O nanofluid of 0.5% volume fraction it is estimated that the size of the radiator, inventory of the fluid, and pumping power is reduced, thus, making this nanofluid an energy efficient fluid for the engine cooling system. © 2015, The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg.Item Thermodynamic irreversibility and conjugate effects of integrated microchannel cooling device using TiO2 nanofluid(Springer, 2020) Narendran, G.; Gnanasekaran, N.; Arumuga Perumal, A.P.Thermal management is highly essential for the latest electronic devices to effectively dissipate heat in a densely packed environment. Usually, these high power devices are cooled by integrating micro scale cooling systems. Most of the works reported in the literature majorly concentrate on microchannel heat sink in which the characteristics of friction factor and enhancement of heat transfer are analyzed in detail. However, due to the advent of compact electronic devices a crucial investigation is required to facilitate an amicable environment for the neighboring components so as to improve the reliability of the electronic devices. Henceforth, in the present study a combined experimental and numerical analysis is performed to provide an insight to determine the performance of a copper microchannel integrated with aluminium block using TiO2 nanofluid for different particle configurations. Needless to say, the present study, which also focuses on entropy generation usually attributed to the thermodynamic irreversibility, is very much significant to design an optimum operating condition for better reliability and performance of the cooling devices. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.Item Computational investigation on the effect of geometrical parameters on thermal energy storage systems(Begell House Inc., 2021) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.The present work is an attempt to understand the effect of geometry on the heating and cooling characteristics of thermal energy storage systems. Three different geometrical models (square, pentagon, and hexagon) were considered and the thermal storage material used was a composite of paraffin wax (98%) and Al2O3 nanoparticles (2%). The heating and cooling processes were analyzed by applying a constant heat flux. Among the three models, the square model showed a faster melting rate but the cooling rate was too steep. The hexagonal model showed optimum results in both the heating and cooling processes with uniform and smooth variations in the liquid fraction and temperature. Hence, for optimal thermal storage applications the hexagonal model (or its geometries), which is close to the circular model, can be considered. © 2021 by Begell House, Inc.Item A Multi-Protocol Home Automation System Using Smart Gateway(Springer, 2021) Chaudhary, S.K.; Yousuff, S.; Meghana, N.P.; Ashwin, T.S.; Guddeti, R.M.R.Smart Home is one of the most established applications of the Internet of Things. Almost every equipment we use in our daily life—appliances, electric lights, electrical outlets, heating, and cooling systems-connected to a remotely controllable network, giving the user’s ability to remotely control and monitor the house, save energy without compromising on comfort and ultimately improve the quality of experience of staying in the house. We present a cost-effective system and address a major challenge that the industry faces today-Protocol Compatibility. To address the challenge, we make use of separate gateways/bridges for each network and an open-source home automation framework called OpenHAB, where each bridge links with a single master Wi-Fi gateway, providing a single window of control through an Application or a web interface for an integrated Smart Home. We integrate an elderly health monitoring device-Beehealth with OpenHAB; addressing the paramount need of a portable, accurate, and efficient health monitoring and fall detection device. We present two methods for fall detection, namely: threshold-based and Neural Network-based, with the latter resulting in 94% accuracy for fall detection. We evaluate the Smart Home devices on parameters like syncing time, battery life, recharge time, deployability, and cost. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.Item Numerical investigation of cooling performance of a novel air-cooled thermal management system for cylindrical Li-ion battery module(Elsevier Ltd, 2021) Kausthubharam, n.; Koorata, P.K.; Chandrasekaran, N.Batteries strongly influence the performance of electric vehicles. Therefore it is crucial to develop a battery thermal system that is highly efficient in removing the battery pack's heat during its operation. In this paper, a numerical analysis of a lumped thermal model coupled with fluid flow equations is employed to investigate the novel air-cooled battery thermal management system (BTMS). The cooling efficiency of the proposed battery thermal system with commercial thermal interface material (3M™) is investigated by comparing it with a standard battery pack at different discharge rates. The proposed solution offers a 25% reduction in peak temperature when compared to the standard one. The thickness of the thermal interface material is found to have an insignificant impact on the battery pack's thermal performance. Introducing forced air-cooling in the battery pack reduced the maximum temperature considerably but increased the temperature difference compared to the battery pack without forced convection. Then the effect of various structural and operational parameters on the performance of the BTMS is investigated. Moving the air inlet-outlet boundaries to a central location increased the uniformity of temperature distribution in the battery pack. Although the increase in the inlet airflow velocity reduces the maximum temperature, it comes at the cost of an increase in temperature difference and power consumption. It is further observed that a reduction in ambient temperature reduces the peak temperature and makes the temperature distribution in the battery pack more homogeneous. The discharge voltage curves indicate a slight reduction in cell potential as a reducing function of temperature. © 2021 Elsevier LtdItem Sustainable reflective triple glazing design strategies: Spectral characteristics, air-conditioning cost savings, daylight factors, and payback periods(Elsevier Ltd, 2021) Gorantla, K.; Saboor, S.; Kontoleon, K.J.; Mazzeo, D.; Maduru, V.R.; Vali, S.V.Buildings with conventional glazing systems are responsible for excessive cooling and heating costs. Sustainable use of energy in building environments requires the use of high-performing opaque and windowed walls. Triple glazing units attenuate solar heat gain/loss compared to single- and double-glazing assemblies, thus reducing air-conditioning costs and greenhouse gas emissions. The optical, energy, economic and environmental performances of a glazing unit are strictly correlated with each other. An improvement of optical properties leads to higher glazing energy performance, cost savings, and greenhouse gas emission mitigations. This work aims to suggest and define an energy-efficient triple glazing unit for lowering cooling and heating costs in buildings while experimentally testing the spectral performance of reflective glasses and assessing heat gains/losses. In this regard, bronze, green, grey, sapphire blue, and gold reflective glasses were considered and settled in sixty different triple glazing combinations. Spectral characteristics of reflective glasses were measured experimentally using a spectrophotometer over the entire solar spectral range (300–2500 nm). For the aims of this investigation, a numerical model was developed to assess the net annual cost saving ($/m2) and the payback period of the examined glazing units for the eight cardinal directions (N, N-E, E, S-E, S, S–W, W and N–W). The results confirmed that the TWG35 window glass unit in the S-E orientation was the most energy-efficient glazing in terms of alleviating this critical challenge (air-conditioning cost-saving 16.72 $/m2 among all other studied window glass units), while a payback period of 2.2 years was revealed. On the other hand, the TWG33 window glass unit has led to the optimal-lowest payback period (2.1 years), with a net annual cost saving of 16.55 $/m2. The findings of this paper demonstrate the significance of triple-glazing design approaches from an economic and environmental point of view. © 2021 Elsevier LtdItem Adsorption and desorption through packed and fluidized clay-based composite desiccant beds: a comparison study(Springer Science and Business Media Deutschland GmbH, 2022) Hiremath, C.R.; Kadoli, R.The present study considers the composite desiccant employing horse dung, sawdust with clay and later impregnating CaCl2 into the host material. The microscopic and spectroscopic experimental methods such as scanning electron microscope (SEM) and X-ray diffraction (XRD) were used to characterize the composite desiccants. The specific heat (Cp) quantification reveals higher values for clay-additives composite desiccants with lower pore volume and larger grain sizes, whereas lower values for clay composite desiccants with higher pore volume and smaller grain sizes. Adsorption–desorption experiments for moisture removal and addition are conducted in a vertical column in static and fluidized states. The desiccant beds are subjected to an initially set value of process air velocity, relative humidity, temperature and mass of bed. Moisture removal capacity, moisture addition capacity and mass transfer coefficient are the parameter indices adopted to measure the heat and mass transfer characteristics of vertical packed and fluidized bed comprising clay-additives-CaCl2 composite desiccants. Comparing packed and fluidized beds, a higher surface area of bed in fluidization improves dehumidification performance and results in higher desorption rates. Experimental results confirmed that clay and clay-additives-based desiccants have desired adsorption–desorption characteristics of a suitable desiccant. The interesting advantage of fabricated clay and clay-additives-based composite adsorbents is that the air exits the desiccant bed at a lower temperature, saving cooling energy requirements of sorption-based systems. © 2022, The Author(s), under exclusive licence to The Brazilian Society of Mechanical Sciences and Engineering.Item EFFECTS OF NANOREFRIGERANTS FOR REFRIGERATION SYSTEM: A REVIEW(Begell House Inc., 2023) Kumar, A.; Narendran, G.; Arumuga Perumal, A.P.In this article various nanorefrigerants have been critically reviewed towards the performance enhancement of the refrigeration system. Research has been more focused on the different techniques to prepare nanorefrigerants. This paper is an attempt to summarize all aspects of nanorefrigerants such as preparation, thermophysical properties, hydrodynamic study, boiling heat transfer, and performance of nanorefrigerants. It also discusses the effects of different nanoparticles on ther-mophysical properties. Nanorefrigerants are a special category of nanofluid, advanced nanotech-nology-based refrigerants that are stable mixtures of nanoparticles and base fluid, which improve thermophysical properties such as heat transfer and pressure drop and bring compactness to the system. This article presents an overview of improving thermal performance by using different nanoparticle blends with different base refrigerants. Further, influential parameters of nanopar-ticles and thermal performance are discussed. This paper also discusses the effects of different nanoparticles such as Al2O3, TiO2, CuO, carbon nanotubes (CNTs), etc., on thermophysical prop-erties. The present situation requires a robust system and refrigerants for required performance. Some refrigerants cannot be used directly. So, this paper deals with using nanorefrigerants for better system performance such as coefficient of performance (COP) enhancement, compressor work reduction, and energy efficiency. It is seen that the use of nanorefrigerants, or nanotechnology-based refrigerants, results in highly effective cooling and thus enhances the thermophysical properties of refrigeration systems. © 2023 by Begell House, Inc. www.begellhouse.com.