Yazar "Sonthalia, A." seçeneğine göre listele
Listeleniyor 1 - 8 / 8
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Basics of heat transfer: Conduction(Elsevier, 2023) Varuvel, E.G.; Sonthalia, A.; Aloui, F.; Saravanan, C.G.In this chapter the fundamental concepts of thermodynamics are presented. The relation of heat to other forms of energy and the energy balance is also discussed. As a system moves from one equilibrium state to another, thermodynamics can provide the information about the amount of heat transfer. It cannot, however, provide any information on how long the process will take. The design engineers, however, are more interested in the rate of heat transfer. Heat transfer can take place through conduction, convection, and radiation. This chapter further discusses the heat transfer through conduction in detail. It is well known that heat transfer through a medium has magnitude as well as direction. The heat conduction rate in a given direction is proportional to the temperature gradient, that is, the temperature varies with distance in the given direction. In general, heat transfer is three-dimensional and time dependent. The temperature in a medium varies with position as well as with time. If the temperature is independent of time, then conduction is in a steady state otherwise it is in a transient state. This chapter also discusses conduction through plane/composite wall, composite cylinder, and fins. For simplicity the analysis is carried out in one dimension under steady-state conditions. Heat conduction under transient conditions for a lumped system is also discussed. © 2023 Elsevier Inc. All rights reserved.Öğe Basics of heat transfer: Convection(Elsevier, 2023) Varuvel, E.G.; Sonthalia, A.; Aloui, F.; Saravanan, C.G.This chapter discusses the mechanism of heat transfer through the motion of the bulk fluid also known as convection. This heat transfer can be either forced or free depending on how the initiation of the fluid motion takes place. In forced convection, a pump or a fan is used to force the fluid to flow through a pipe or over a surface. While fluid motion by natural means such as buoyancy (warmer fluid rises) takes place in natural convection. Another way of classifying convection is it can be either external or internal. When a fluid flows over a surface it is known as external flow and when it flows through a duct it can be classified as internal flow. © 2023 Elsevier Inc. All rights reserved.Öğe Basics of heat transfer: Heat exchanger(Elsevier, 2023) Varuvel, E.G.; Sonthalia, A.; Aloui, F.; Saravanan, C.G.Heat exchangers facilitate the exchange of heat between two fluids having different temperatures. The heat exchange involves conduction between the walls separating the fluids and convection in each fluid. The chapter starts with the discussion on classification of heat exchangers. Then the overall heat transfer coefficient and log mean temperature difference (LMTD) for different configurations of heat exchanger is discussed. As the heat exchanger gets fouled over a period of time a fouling factor is introduced that considers the variation in LMTD. Similarly, a correction factor is introduced for multi-pass arrangements. The effectiveness—number of transfer units (NTU) method is also discussed for analyzing the heat exchanger when the outlet temperature of the fluids is unknown. Lastly, selecting the heat exchanger for a particular application is also briefly discussed. © 2023 Elsevier Inc. All rights reserved.Öğe Effect of intake port design modifications on diesel engine characteristics fuelled by pine oil-diesel blends(Taylor and Francis, 2022) Malaiperumal, V.; Saravanan, C.G.; Raman, V.; Kirubagaran, R.K.; Pandiarajan, P.; Sonthalia, A.; Varuvel, E.G.The effect of the modified intake port with various inclined nozzle angles such as 30°, 60°, and 90° on the diesel engine characteristics when operated with pine oil-diesel blends is investigated. Prior to the engine experimental study, a computational analysis was performed to investigate the impact produced on the flow field parameters of an engine due to modified intake port design. The numerical study revealed increased swirl velocity and turbulence for intake port with a 60° single-pass configuration compared to other design configurations. With evidence of improved swirl velocity and the proposed modified intake port design from the numerical study, an experimental investigation was performed using pine oil blends in the diesel engine with modified intake port configurations. The preliminary engine test findings with standard intake port design indicated that P50 (50% pine oil + 50% diesel) has higher peak engine cylinder pressure and heat release rates than P10 (10% pine oil + 90% diesel). Additionally, the 60° single-pass configuration showed further increase in peak pressure and peak heat release followed by standard and other intake port design configurations. At high load, the P50 blend showed a 12.3% increase in BTE for 60° intake port design configuration in comparison to the standard design configuration. While for the same blend, the engine out emissions like hydrocarbon (HC) and smoke were reduced by about 6.6% and 17.6%, respectively, and nitrogen oxide (NOX) emission was increased by 29% for the 60° single-pass configuration when compared to the standard design configuration. Overall, the intended intake port design modification strategy increased the swirl velocity and turbulence, which improved the air/fuel mixing and combustion. This study identifies 60° single-pass configuration as an optimum design on account of the aforementioned improved engine combustion, performance, and emissions. © 2022 Taylor & Francis Group, LLC.Öğe Handbook of Thermal Management Systems: E-Mobility and Other Energy Applications(Elsevier, 2023) Aloui, F.; Varuvel, E.G.; Sonthalia, A.Handbook of Thermal Management Systems: e-Mobility and Other Energy Applications is a comprehensive reference on the thermal management of key renewable energy sources and other electronic components. With an emphasis on practical applications, the book addresses thermal management systems of batteries, fuel cells, solar panels, electric motors, as well as a range of other electronic devices that are crucial for the development of sustainable transport systems. Chapters provide a basic understanding of the thermodynamics behind the development of a thermal management system, update on Batteries, Fuel Cells, Solar Panels, and Other Electronics, provide a detailed description of components, and discuss fundamentals. Dedicated chapters then systematically examine the heating, cooling, and phase changes of each system, supported by numerical analyses, simulations and experimental data. These chapters include discussion of the latest technologies and methods and practical guidance on their application in real-world system-level projects, as well as case studies from engineering systems that are currently in operation. Finally, next-generation technologies and methods are discussed and considered. © 2023 Elsevier Inc. All rights reserved.Öğe Need of battery thermal management systems(Elsevier, 2023) Sonthalia, A.; Varuvel, E.G.; Aloui, F.; Saravanan, C.G.Due to thermal runaway issues, the thermal safety of lithium ion battery has always been a concern all over the world. The cell is highly sensitive to temperature and has a narrow operating temperature range. At different temperatures, complex electrochemical reactions take place. The effect of ambient temperature in different seasons and internal heating can cause side reactions leading to thermal runaway which should be considered while designing the battery thermal management system. This chapter focuses on the cause of thermal runaway at all temperature ranges. Such as at low-temperature capacity fade and lithium dendrite and plating can occur causing internal short circuits. At normal temperature range, side reactions can speed up, reducing the battery life while thermal runaway can occur at high temperatures. © 2023 Elsevier Inc. All rights reserved.Öğe NOx emission reduction in low viscous low cetane (LVLC) fuel using additives in CI engine: an experimental study(Springer Science and Business Media Deutschland GmbH, 2024) Sonthalia, A.; Varuvel, E.G.; Subramanian, T.; Kumar, N.This study examines the combustion properties of pine oil (PO), which is classified as a low viscosity, low cetane (LVLC) fuel. It highlights the superior performance of pine oil in comparison to diesel fuel, but acknowledges that its low cetane index causes a delay in combustion initiation, which consequently results in elevated NOx emissions. Fuel atomization, evaporation, and air/fuel mixing are enhanced by the reduced viscosity and boiling point of PO in comparison to diesel. Nevertheless, the low cetane index of PO restricts its applicability as a diesel fuel substitute in CI engines. Due to significant heat release after an extended ignition delay, NOx emissions tend to rise with less viscous and low cetane (LVLC) fuels. A range of cetane improvers, such as diethyl ether (DEE), benzyl alcohol (Bn), diglyme (DGE), and methyl tert-butyl ether (MTBE), have demonstrated effectiveness in mitigating nitrogen oxide (NOx) emissions upon introduction into pine oil. All the cetane improvers were added 5% and 10% by volume with pine oil. A twin-cylinder tractor engine operating at a constant speed of 1500 revolutions per minute was utilized in this testing. In order to achieve a warm-up condition that would enable the smooth operation of PO, the engine was initially operated on diesel fuel. At maximum load condition, NOx emission of PO was higher by 8% in comparison to diesel. NOx emission was significantly reduced with addition of cetane improvers. Maximum reduction of 7% was observed with PO + MTBE 10% in comparison to PO which is in par with diesel. An increase in HC and CO emission was observed with all cetane improver addition with PO. Graphical abstract: (Figure presented.). © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2024.Öğe Some studies on reducing carbon dioxide emission from a CRDI engine with hydrogen and a carbon capture system(Elsevier, 2022) Varuvel, Edwin Geo; Thiyagarajan, S.; Sonthalia, A.; Prakash, T.; Awad, S.; Aloui, F.The increased use of fossil fuels in the transportation sector has led to an exponential rise of carbon dioxide in the atmosphere. The carbon dioxide (CO2) is the major cause of global warming resulting in climate change and extreme weather conditions. This study explores the ways of reducing the CO2 emission from the exhaust of a common rail engine. The reduction in CO2 emissions were achieved by a combination of methods. It includes the use of low carbon biofuels (cedarwood oil (CWO), and wintergreen oil (WGO)), induction of zero-carbon, hydrogen in the intake manifold and a zeolite-based after-treatment system. In diesel, CWO and WGO were blended 20% by volume and experiments were conducted at different load conditions. The results shows that 20% blending of winter green oil resulted in maximum CO2 reduction of 20% as compared to diesel. The emission was further reduced with the induction of hydrogen along with the after-treatment system. It is seen that a maximum of 54% reduction in CO2 emission could be achieved with the combination for WGO in comparison to diesel without much affecting the other emissions and performance parameters. © 2021 Hydrogen Energy Publications LLC
