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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.

The Exhaust Noise is one of the major noise pollutants. It is well-known that for higher noise reduction, the engine has to bear high back pressure. For a race car, back-pressure plays a major role in engine's performance characteristics. For a given condition of engine rpm & load, conventional muffler has a fixed value of back-pressure and noise attenuation. Better acceleration requires low back-pressure, but the exhaust noise should also be less than the required (Norm) value (110 dBA). This contradicting condition is achieved here by using a ‘Butterfly Valve’ in this novel exhaust muffler. The butterfly valve assumes 2 positions i.e. fully open & fully closed. When the valve is fully closed, the noise reduction will be higher, but the back-pressure will also shoot up. When open, noise reduction will be less and so the back-pressure. So, when better performance is required, the valve is opened and back-pressure is reduced. The muffler is designed for a 4 cylinder 600 cc engine.

For zero tail pipe emission transportation, fuel cell technology is the best available option for replacing commercial IC engines. Worldwide lot of research work is going on in development of fuel cell vehicles. This work deals with the virtual development of system architecture for hybrid electric - fuel cell light commercial vehicle. The goal of this research work is to virtually design, model and convert an existing LCV model in to a hybrid electric fuel cell vehicle for the same performance and better efficiencies with zero tail pipe emissions. A unique fuel cell management system is developed and used for obtaining better efficiencies. A mathematical model of the vehicle is developed using GT-Drive which tracks the energy flow and fuel usage within the vehicle drivetrain. The vehicle is tested on chassis dynamometer to provide data for validation of the mathematical model. Model results and vehicle data show good correlation when validated.

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.

The work presented in this paper deals with the use of non-linear FEA simulation in powertrain development. Prediction of cylinder bore distortion early in the design stage significantly affects overall performance of engine as bore distortion directly affects oil consumption, blowby and emission. The paper presents a methodology for predicting bore distortion with an objective of achieving improved performance of powertrain. For this purpose detailed Finite Element Model of Engine Assembly was prepared, nonlinear interaction between powertrain mating parts was captured by defining contacts, physical behaviour of gasket was captured through experimental testing by extracting loading and unloading pressure closure curve and the same data was used as an input for defining gasket nonlinear properties. Physical assembly sequence was captured by carrying out sequential analysis.

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.

In the pursuit of design and development of efficient, reliable and durable system and components for modern engines, there is a need to understand complications involved in building mathematical models for simulation. Valve train and timing drive systems are having higher rankings for addressing these attributes. Hence, a new comprehensive multi body dynamics model is built and equations are solved by state-variable approach. Model developed is validated and in order to probe into details of Hydraulic Lash Adjuster (HLA) behavior and coupled analysis of timing chain drive systems for valve train system, simulation is carried out to freeze design options. Engine timing drives used in engines are one of the most critical systems. Timing chains are preferred widely in modern high speed engines as compared to timing belts and gear drives. In spite of advantages of chain drive systems, their complex dynamic behavior is not well researched.

Development of future efficient and cleaner heavy duty engines are no longer limited to laboratory development under standard conditions. In order to address the global issues like climate change and poor air quality in its true sense, future advanced and existing heavy duty diesel engines should also be demonstrating emission conformity compliance as per legislations under real driving conditions using PEMS testing. In India starting from Apr 2023, heavy duty vehicles would be tested for in-service conformity and presently they are under monitoring phase. With the introduction of RDE (Real Driving Emission) the effort, cost and time requirements could be tremendous in order to meet conformity compliance over real driving conditions including the range of ambient conditions for the said period as per the norms.

In the quest towards meeting stringent emission norms as well as robust performance requirements, there is an ever growing need to continually research into and develop high caliber engines. This necessitates handling huge amounts of generated test data that monitors a multitude of variables like engine speed, combustion chamber pressure, engine load and the like. Further, in order to establish the scalar engine performance parameters like efficiency, Brake Mean Effective Pressure, Indicated Mean Effective Pressure, P-V diagram, post processing is required to be done on the measured test data that involves complex calculations like numerical integration and other mathematical operations on a grand scale. In order to meet this objective, the authors hereby showcase a knowledge based algorithm that integrates and streamlines the entire procedure from handling of the huge test data to performing all the calculations in order to arrive at the scalar engine performance parameters.

Electric Power Assist Steering (EPAS) is a safety critical system because it affects vehicle stability and dynamics. In EPAS, electric motor takes the power from the battery and delivers this power to rack and pinion only on demand. Since EPAS contains electrical component such as Motor and electronic component such as Electronic Control Unit (ECU), reliability of these components is very important. To ensure safety and reliability, ISO 26262 standards are adapted which are derived from IEC 61508. This standard regulates the product development on system, hardware and software level and manages functional safety for electrical and electronic components. This paper discusses the applicability of the ISO 26262 standard to the development of EPAS ECU with respect to its hardware and software design. Hazard analysis and risk assessment of the basic EPAS architecture is performed and architecture is improved to achieve safety goal as per the standard.