Increasing pollution all over the world has led to stringent emission norms and development of more environment friendly technologies. In near future, rapid transition towards greener and cleaner technologies is anticipated by automotive organisations. In India, FAME (Faster Adoption and Manufacturing of Electric Vehicles) scheme by NITI Aayog has made the intent about the usage of Hybrid & Electric vehicles (EV) clearer. As range is a major concern in EVs, the component that has become the subject of major interest is Battery due to its energy storage ability. Choosing batteries depends on energy density, weight and cost, which makes Li-ion battery technology leading option among others due to its better Power density v/s Energy density relations. For optimum performance and safety, one of the major concerns in the development of lithium-ion (Li-ion) battery packs for EVs is thermal management.
Valve seat inserts (VSI) are installed in cylinder heads to provide a seating surface for poppet valves. Insert material is more heat and wear resistant than the base cylinder head material and hence it makes them better suited for valve seating and improved engine durability. Also using inserts permits easier repair or rebuild of cylinder heads as only the wear surfaces need to be replaced. Desirable performance characteristics are appropriate sealing, heat-transfer and minimizing valve to VSI wear and undesired outputs include valve seat dropping and cracking. With downsizing trend of diesel engines, it leads to increasing power density and therefore higher cylinder pressure and temperatures. Hence the engine components are getting exposed to more severe loadings and hence to failure modes, which were not heretofore experienced based on the warranty data.
The shift over of the automobile sector from the ICE to the electric drives is imminent due to arising global issues of pollution and ever rising pressure on the demand of the natural resources due to lower efficiency of the ICE drives. This has led to uprising of the Lithium-ion batteries, with addition of the burden of living to expectation of clean energy and higher efficiencies. Alongside, with limitation in the availability of the lithium-ion batteries they carry a hefty price tag with them, hence causing huddles in the research. Lack of research leads to failure of batteries and may cause life threatening situations when operating in the vehicle. In order to insight the working of the cylindrical lithium-ion batteries under different driving and environmental conditions a methodology is developed for the coupled electro-chemical and thermal phenomenon. This allows anticipating the behaviour of the battery under different conditions that influence its performance.
The increase in the global warming potential and increase in the pollution rate; people tend to adopt an alternative for the internal combustion engine vehicles. And the alternative leans toward electric vehicle technology. The pure electric vehicle technology also has the limitations of lesser energy storing capacity and higher charging time; needs further improvement. The advancements are Fuel Cell Electric Vehicles (FCEV) helps the vehicles to have a higher range and lesser filling time. The efficient thermal management system in FCEV lead higher energy utilization and increased vehicle range. This paper deals with the significance of thermal management energy consumption on the range and effective working of the FCEV System.
Affordable, efficient and durable catalytic converters for the Commercial Vehicle and Non-Road industry in all countries are required to reduce vehicle emissions under real world driving conditions and fulfill future legal requirements. Specially for India traffic conditions and payload to engine size conditions new cost-effective solutions are needed to participate in a cleaner and healthier environment. Metallic substrates with structured foils like the Transversal StructureTM (TS) or the Longitudinal StructureTM (LS) have been proved to be capable of improving conversion behavior, even with smaller catalyst size. Now Vitesco Technologies is developed a new Substrate for Heavy duty applications that specifically maintains the geometric surface area at a very high level and improves further the mass transport of the pollutants, which potentially leads together to very high pollutant conversion rates.
Till recently supercharging was the most accepted technique for boost solution in gasoline engines. Recent advents in turbochargers introduced turbocharging technology into gasoline engines. Turbocharging of gasoline engines has helped in powertrains with higher power density and less overall weight. Along with the advantages in performance, new challenges arise, both in terms of thermal management as well as overall acoustic performance of powertrains. The study focuses mainly on NVH aspects of turbocharging of gasoline engines. Compressor surge is a common phenomenon in turbochargers. As the operating point on the compressor map moves closer to the surge line, the compressor starts to generate noise. The amplitude and frequency of the noise depends on the proximity of the operating point to the surge line. The severity of noise can be reduced by selecting a turbocharger with enough compressor surge margin.
The Common Rail Fuel Injection System (CRS) has completely changed the whole diesel engine combustion cloud dynamics and enhanced the applicability of diesel engines further with a motto of providing a more cleaner sky and greener earth. The most cutting-edge technological developments made in CRS and EGT system enables OEMs to achieve further more stringent emission norms and adopt the environmental protection compliances. Today’s CRS systems are the most advanced generation fuel injection systems providing further high injection pressures, wide multiple injections capability with shorter dwell periods enabling real smoother Digital Rate Shaping (DRS) benefits and Smart thermal management of exhaust systems while meeting stringent emission compliances and achieving future CO2 reductions goal. Initial DRS I system developments were tried with a dwell period up to 500us-800us due to injector durability life limitations.
During the cold start conditions engine must overcome higher friction loss, at the cost of fuel penalty till the optimum temperatures are reached in coolant and lubrication circuits. The lower thermal capacity of the lubrication oil (with respect to the coolant) inverses the relation of viscosity with temperature, improves engine thermal efficiency benefit. Engine oil takes full NEDC test cycle duration to reach 90°C. This leads to higher friction loss throughout the test cycle, contributing a significant increase in fuel consumption. Increasing oil temperature reduces viscosity, thereby reducing the engine friction. This helps to identify the focus for thermal management in the direction of speeding up the temperature rise during a cold engine starting. This work aims at the study and experiment of an exhaust recovery mechanism to improve the NEDC fuel economy.
With the rising emission level in Indian cities, the focus on pure battery electric vehicle is increasing also in India. The Government of India his also focusing on preparing right policies like FAME-2 to promote the acceptability of EV's by providing subsidies as well as creating the required infrastructure. The environmental conditions in India is much different than other developed countries of Euro, China etc. The max. temperatures in India can go up to 55℃ in the hottest summer time, while during winters temperature can go up to <-25℃ in the northern Himalia region. In these conditions the cooling system of the electric-powertrain components like E-Machine Battery pack etc have to be protected for worst case scenarios specific to Indian conditions. Major cost driver of EV's lie in the HV battery packs and it is very important for acceptability of EV's that the Battery is maximized.
Abstract: Electrification is one of the megatrends across the industries, like electric vehicles, more electric aircraft, electric vehicles etc. which needs advancement in power electronics component technology. As technology advances in miniaturization of power electronics, thermal-management issues threaten to limit the performance of these devices. These may force designers to derate the device performance and ultimately these compromise in design may increase the size, weight of the application. One of the technologies capable of accomplishing these goals employs a class of materials know as metal foam. Metal foams are lightweight cellular materials inspired by nature. The main application of metal foams can be grouped into structural and functional and are based on several excellent properties of the material. Structural applications take advantage of the light-weight and specific mechanical properties of metal foam.
To study the functioning of a fuel cell and optimize its operating parameters to achieve the best efficiency in operation it is important to have a robust fuel cell model that can simulate the behavior of the fuel cell stack under various operating conditions. The operating voltage of the fuel cell at different current densities depends upon thermodynamic parameters like temperature and pressure of the reactants as well factors like the state of humidification of the electrolyte membrane. A 1D model is developed to capture the variation in voltage at different current densities due to internal losses and changes to operating conditions like temperature and pressure. Additionally since the stack temperature and moisture content within the stack influence the stack operation directly models for the thermal management of the stack and humidification of the membrane are also developed.
The automobile sector is moving towards electrification as a replacement for the conventional IC Engine as the power source of vehicles. In electric vehicles, Li-ion battery is the widely used energy source for traction and is a major differentiator among various sub components that affect vehicle performance, safety and efficiency. The life of the battery pack is affected by different stress factors like SoC (state of charge), DoD (depth of discharge), C-rates (charge and discharge currents) and battery temperature. Out of the mentioned stress factors, the life of batteries is most influenced by the temperature excursion seen by the li-ion cells in the battery pack. There are various thermal management strategies available to keep the temperature under control like air cooling , chilled liquid cooling and hybrid cooling systems.
Technology improving on a daily base, the innovating structures and development of LED’S has led to dramatic improvements of the performance in LED technology. Replacing incandescent lights and CFLs clearly concludes the character of the LED. Producing high lumen output and efficiency has been the greatest advantage. Every industry including automobile is slowly shifting from halogen lamps to LED lamps. LED producing localized heat and maintaining the junction temperature for maximum lumen output range causing failure of LED has been the greatest hurdle for the engineers. Researches carried out in order to minimize the disadvantages are the main focus in lighting industry. In traditional methods, Thermal management of LED’s are done by passive cooling of LED using heat sinks and fluids such as coolant based heat sink model.
For long-haul heavy-duty transport, ICE (Internal Combustion Engine) propulsion will continue to play a dominant role. Fossil Diesel fuel with its high energy density, even made of biogenic or synthetic source, will not remain the prime and cost-efficient solution under always more stringent emission limits for greenhouse gas and pollutants. Our assessment of all relevant alternative fuels from renewable source resulted in DME (Dimethyl-ether) being the most promising fuel for long-haul applications. DME shows one of the best compromises regarding energy density, emission reduction potential and production cost. In particular, DME fuel in a compression ignition engine achieves similar thermal efficiency as a diesel fuel but with significantly lower CO2 emissions (TtW) due to the favourable H/C ratio and potentially down to zero (WtW) if produced from bio- or renewable sources.
The effects of a controlled coolant flow rate variation on knock tendency are investigated on a small S.I. engine. The analysis concerns the transient behavior of the unburned gas temperature to a controlled variation in the coolant flow rate. This phenomenological investigation aims at preventing knock through a proper thermal management as an efficient alternative to the currently adopted strategies. Moreover, the proposed approach is particularly useful for hybrid-electric powertrain, where the engine is expected to operate in the highest efficiency region by adopting high compression ratios and full stoichiometric map. The analysis was carried out through an experimental campaign, where the control of cylinder wall temperature was achieved by means of an electrically driven water pump. The spark advance and the air/fuel ratio were properly varied in order to operate with advanced spark timing and stoichiometric mixture at full load.
The use of Ducted Fuel Injection (DFI) for attenuating soot formation throughout mixing-controlled diesel combustion has been demonstrated impressively effective both experimentally and numerically. However, the last research studies have highlighted the need for a tailored engine calibration and of a duct geometry optimization for the full exploitation of the technology potential. Nevertheless, the research gap on the response of DFI combustion to the main engine operating parameters has to be still covered. Previous research analysis has been focused on a numerical soot-targeted duct geometry optimization in constant-volume vessel conditions. Starting from the optimized duct design, the herein study aims to analyze the influence of several engine operating parameters (i.e. rail pressure, air temperature, air density, oxygen concentration) on DFI combustion, having free spray results as a reference.
BYD recently introduced its new DM-i (Dual Mode Intelligent) hybrid platform with a new dedicated 1.5NA high-efficient engine, which has a peak brake thermal efficiency of 43%. This platform is electric-driven primarily and the engine only starts on demand. This requires that once started, the engine can reach its best working temperature as quick as possible. To achieve this target, BYD designed a new intelligent thermal management system. This system adopted an advanced split cooling strategy to control the flow ratio between the cylinder block and head, which was realized by a combination of one electric thermostat and one traditional wax thermostat. An electric water pump was used to actively control the coolant flow rate of the system.
One challenge for the development of commercial vehicles is the reduction of CO2 greenhouse, where hydrogen can reduce the fleet CO2. For instance, in Europe a drop in fleet consumption of 15% and 30% is set as target by the regulation until 2025 and 2030. Another challenge is EURO VII in EU or even already approved CARB HD Low NOx Regulation in USA, not only for Diesel but also for hydrogen combustion. In this study, based on future emission regulations, first the requirements for the combustion and after-treatment system of a hydrogen engine are defined. The major advantages regarded to hydrogen combustion are due to the wide range of flammability and very high flame speed numbers compared to fossil based fuels. Thus, it can be well used for lean burn combustion with much better fuel efficiency and very low NOx emissions. A comprehensive experimental investigation is performed on a HD 2. L single-cylinder engine.
SAIC Motor Corporation Limited (SAIC Motor) has developed an all new 2.0 L 4-cylinder turbocharged gasoline direct injection engine to meet the market demand and increasingly stringent requirement of CAFE and tail-pipe emission regulations. A series of advanced technologies have been employed in this engine to achieve high efficiency, high torque and power output，fast response low-end torque performance, refined NVH performance, all at market leading level, and low engine-out emissions. These main technologies include: side mount gasoline direct injection with 35MPa fuel injection system, integrated exhaust manifold, high tumble combustion system, 2-step intake variable valve lift (DVVL) with Miller Cycle, efficient turbo charging with electric wastegate (EWG), light weight and compact structural designs, NVH measures including balancer system with silence gear, friction reduction measures, optimized thermal management, etc.