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The infliction of rigorous emission norms across the world has made the automobile industry to focus and dwell upon researches to reduce the emissions from internal combustion engines, namely diesel engines. Variation in fuel injection timing has better influence on reduction of engine exhaust emissions. This papers deals with the variation of fuel injection timing along with fuel injection pressure numerically on a 4 stroke, single cylinder, and direct injection diesel engine running at full load condition using CONVERGE CFD tool. As the piston and bowl geometry considered in this work is symmetric, only 60 degree sector of the piston cylinder assembly is considered for numerical simulation over complete 360 degree model.

Thermal management is one of the most challenging and innovative aspects of the automotive industry. The efficiency of the vehicle cooling framework unequivocally relies upon the air stream through the radiator core. Significant advances in thermal management are being embraced in the field of radiator material and coolant. The radiator shouldn't be exclusively credited for the reliable cooling of the engine. There are other auto parts that play an essential role in keeping engine temperature at a manageable level. The fan-shroud assembly is an important component of the cooling system. While the fan is responsible for drawing in air, the fan shroud's job is to ensure uniform air distribution to the radiator core. By assisting airflow in the engine compartment the fan shroud helps in dismissing excess heat from the engine. This assembly also prevents the recirculation of heated air through the cooling fan.

The present work is concentrated to study the effect of varying inlet pressures on the dynamics of the suction valve obtained from a hermetic reciprocating compressor. The effect of valve functioning on the efficiency of a compressor is highly acceptable. Rather than the delivery valve, the suction valve has a significant impact on the compressor efficiency. The reed valve in a hermetic compressor is a cantilever type arrangement. The valve operates due to the pressure difference between the suction muffler and the cylinder. The numerical analysis which includes Fluid-structure interaction is used in the present study. The flow and structural domain employed in the present study are modelled with Solidworks 15.0. The fluid structure interaction analysis is a combination of ANSYS Fluent and ANSYS structural. These two are coupled with a system coupling in ANSYS Workbench 16.0. The numerical results obtained from the simulation are validated with the experimental data.

In Formula Student, the vehicle working parameters are quite disparate from that of a commercially designed vehicle. The inability of teams to incorporate the atypical running conditions in their design causes multiple unforeseen issues. One such condition where the teams fail to improvise upon is the cooling system. Due to the high performance requirement of the competition, multiple teams participating face recurring heating problems. Maximum efficiency from a combustion vehicle can only be achieved when the cooling system is designed to handle the increasing power demand. This paper brings forth a detailed study on the intricate design of the cooling system. The problem has been approached using both theoretical and simulation models. Firstly, NTU-ℇ method was used to calculate the overall heat transfer coefficient and the temperature drop through the radiator core.

At present, the emissions from an internal combustion engine exhaust is reduced by exhaust after treatment devices. However, after treatment devices like SCR which is used to control NOx, results in additional weight, high costs and rejects toxic gases like ammonia etc. To overcome this problem, a new combustion technique should be developed to improve the primary combustion processes inside the combustion chamber itself to reduce these exhaust gas emissions. This work presents the results of such a technique that is applicable to direct injection, Diesel engines. The technique is based on the porous medium combustion (PMC) technology, which is developed for steady state household and industrial combustion processes. Based on the adiabatic combustion in porous medium (PM), a porous medium in engine piston as a concept is proposed here to achieve improved combustion efficiency and low emissions. Using a commercial code CONVERGE the entire cycle is simulated and presented here.

The present world persists with a twin crisis of energy consumption and the environmental degradation. Finding a compromise between them provides a breakthrough in the research in energy containments of the engine attachments. Oil pump has role of providing the transmission of oil to other engine parts and acts as the coolant for the moving parts. Conventional oil pump with pressure relief valve is its loss lot of energy in oil re-circulation due to the discharge effect. On contrary, the variable displacement oil pump has an effect on reduction of oil pressure using eccentric ring without having any compromise with the energy consumption. This paper proposes model and experimental methodology of a variable displacement Gerotor oil pump for lubricating the internal combustion engine. This particular unit is performed extremely in terms of rotational speed, delivery pressure and displacement variation.

Agriculture is a backbone of country’s economy. To increase the crop production efficiency weeds are to be removed. The present weeding machines are different in dimension which may not be suited to small and medium field farmers, due cost effectiveness and dimensions. This work presents the development of sugarcane weed remover (SWR) and its performance investigation to improve the weed removal rate. The SWR is an application specific machine, it consists of single cylinder air cooled gasoline engine, blade assembly and transmission system. In order to improve SWR efficiency different blade profiles are theoretically analysed. The optimised blade profile is employed in the weed remover which offers fuel consumption of 0.11 g/(KW.h). The SWR on-field experience confirmed that the field capacity and efficiency in weeding is 0.0025 ha/hr and 60% respectively.

Though high thermal conductivity polymer composites are prepared based on the thermal requirements, the effectiveness and overall heat transfer performance of the radiators have to be addressed comprehensively to validate the concerned efforts taken to prepare the high thermal conductivity polymer composites. In this article, theoretical analysis on the thermal performance of the cross flow type heat exchanger under convection is performed only by concentrating on the term thermal conductivity of the material. Micro channel based geometry is extracted from the given heat exchanger problem to reduce the complexities of simulation. The term cooling system performance index (CSPI) is used to achieve the expected targets in the present investigation. For shorter fins, the effect of thermal conductivity on the cooling system performance index under lower Reynolds number is insignificant.

This paper describes the design methodology and algorithm development towards the design of an automatic external gear-shifting and clutch-actuation system for a sequential gearbox with the aim of providing the drivers with easier and an efficient means of shifting gears. Automatically actuated manual transmission system bridges the gap between automatic and manual transmissions which provides the advantages of both type of transmissions. This would ideally leads to faster shifting time and provide significant benefits in the form of electronic-aids like launch control and traction control. Removal of mechanical clutching would reduce fatigue and lead to ergonomic benefit. Based on the benchmarking performed on an easily available ready-to-install aftermarket alternative, options will be considered for the actuating mechanism and the most feasible will be used to develop a shifting system.

In present commercial vehicles, the cranking torque required for a heavy duty compression ignition engine is very high. This results in higher durability and reliability requirement of cranking system components and also makes it cumbersome to implement start-stop micro hybrid feature which requires more number of cranking cycles in lifetime. Hence higher capacity starter motor and battery is being used for implementing start-stop feature. However this would result in cost and packaging issues. In order to implement start-stop feature maintaining the same starter motor and battery capacity, the cranking energy demand of the engine needs to be reduced. Studies conducted shows that the major source of breakaway torque is the work done in compression stroke during a starting cycle.

The desire for higher fuel economy, improved performance and driveability expectations of customers from engines are gradually increasing along with stringent emission regulations set by the government. Many original engine manufacturing companies are prompted to consider the application of higher function variable valve actuation mechanisms in their next generation vehicles as a solution. The VVA is a generalized term used to describe any mechanism or method that can alter the shape or timing of a valve lift event within an internal combustion engine. The VVA allows lift, duration or timing (in various combinations) of the intake and/or exhaust valves to be changed while the engine is in operation. Engine designers are prompted to consider Variable Valve Actuation (VVA) system because of the inherent compromises with fixed valve events. The major goal of a VVA engine is to control the amount of air inducted into the engine which is a direct measure of torque.

Electronic throttle body (ETB) is commonly employed in an intake manifold of a spark ignition engine to vary the airflow quantity by adjusting the throttle valve in it. The actual position of the throttle valve is measured by means of a dual throttle position sensor (TPS) and the signal is feedback into the control unit for accomplishing the closed loop control in order handle the nonlinearities due to friction, limp-home position, aging, parameter variations. This work aims presents a neural networks based novel virtual sensor for the estimation of throttle valve position in the electronic throttle body. Proposed neural network model estimates the actual throttle position using three inputs such as reference throttle angle, angular error and the motor current. In the present work, the dynamic model of the electronic throttle body is used to calculate the current consumed by the motor for corresponding throttle valve movement.

The concept of camless engines enables us to optimize the overall engine efficiency and performance, as it provides great flexibility in valve timing and valve displacement. This paper deals with design of camless engines with pneumatic actuator. The main objective is to build a prototype and test its performance at different engine speeds. Also an extensive research on the sensors is done to detect the various sensors that could be used to identify the crankshaft position. Here the features and advantages over conventional engines are discussed. In addition the overview of the camless system in the engine is focused along with the design principle and the components used. The system thus designed is capable of actuating at 1500 rpm and demonstrates the ability of pneumatic actuators to be used in an internal combustion engine with low rpm needs.

A Formula student team aims to develop and improve their designs every year, as far as the powertrain aspect is considered performance output and enhancement is the primary aim, and for engine to perform better, the health of the engine is the most important parameter; hence the lubrication system of the vehicles powertrain should be improved to get the most out of the engine. The primary challenge for the development of a new lubrication system was the inability to replicate the performance given by stock wet sump with the self-designed custom dry sump. However, the advantages can outnumber the cons of implementing a custom dry sump lubrication system. The work brought together in this paper highlights the meticulous design procedure for implementing a custom made dry sump system onto a 4-cylinder in-line Honda CBR600RR engine.