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This work is a part of program on “Development of High Performance DI, 3 Cylinder CRDI Diesel Engine to meet Euro-IV/V Emission Norms focused on automotive passenger car application purpose. This is a 3 Cylinder, TCIC engine designed for combustion pressure of 160 bar max for first stage which is being upgraded to 200 bar max in the second stage. Cylinder Head design is a part of complicated configuration whose construction and principal dimensions are dependent on the size of inlet and exhaust valves, fuel injectors positioning and mounting, port layout and swirl and shape of combustion chambers. The cylinder head of a direct-injection diesel engine has to perform many functions. It has to bring charge air to the cylinder and exhaust gas from the cylinder, with minimum pumping loss and required swirl and other properties of charge motion.

Diesel powered electric generators are used in a variety of applications, such as emergency back-up power, temporary primary power at industrial facilities, etc. As regulatory and customer requirements demand quieter designs, special attention is given to the design of acoustic enclosures to balance the need of noise control with other performance criteria like ventilation and physical protection. In the present work, Statistical Energy Analysis (SEA) approach augmented by experimental inputs is used to carry out Vibro-acoustic analysis of an enclosure for higher capacity Diesel generator set. The exterior sound radiated from an enclosed generator is predicted and further enclosure is optimized for an improved sound-suppression. The airborne sources such as engine, alternator, radiator fan and exhaust are modelled explicitly using experimental noise source characterization. Structure borne inputs are also captured in the test for improving modelling accuracy.

A methodology for design and development of radiator cooling fan is developed with an objective to improve underhood thermal management. For this purpose an Axial Fan Design Software has been developed which is based on Arbitrary Vortex Flow theory. The software is useful for obtaining initial blade design for the given basic functional requirements in terms of Airflow, Pressure Rise and Speed which defines the operating point of the fan. CFD analysis of the initial fan design is then carried out to predict the fan performance curve. Computation model resembles a fan set up in a wind tunnel. Further, Parametric Optimization is carried out using CFD to meet the functional requirements. A Rapid Prototype sample of the optimized fan design is manufactured and tested in a fan test rig made as per AMCA 210-99 standard to evaluate the fan performance curve and the power consumption.

Virtual modeling of engine and predicting the performance and emissions is now becoming an essential step in engine development for off-road application due to the flexibility in tuning of the combustion parameters and requirement of shorter development times. This paper presents an approach where the test bed calibration time is reduced using virtual techniques, such as 1D thermodynamic simulation and 3D CFD combustion simulation for 4 cylinders TCIC engine complying with Stage IIIA emission norms. 1D thermodynamic simulation has played an important role in the early stage development of an engine for selection of engine sub systems like turbocharger, manifolds, EGR system, valve timings etc. The application of 1D Simulation tool for combustion system development, focusing on NOx emissions for an off road multicylinder mechanical injection diesel engine is discussed.

New process development of forging component requires in-depth knowledge and experience related to the process. Also it requires number of physical trials to arrive at optimum process and initial billet dimensions. With the help of reliable computer simulation tool, it is possible to optimize the complete forging process and billet dimensions. Simulation provides much more insight about the process and possible forging defects. This saves considerable time and money. This paper describes about a complete forging process designed for a complex component. With the help of metal forming simulation software, complete forging process was simulated and optimized. Forging defects were removed during optimization of the process. Billet weight optimization was also carried out. Deciding the preforming shape of the billet was the main challenge. An innovative pre-forging shape was arrived which resulted in eliminating one process stage.

Forging is a metal forming process involving shaping of metal by the application of compressive forces using hammer or press. Forging load of equipment is an important function of forging process and the prediction of the same is essential for selection of appropriate equipment. In this study a hot forging material i.e. 42CrMo4 steel is selected which is used in automotive components like axle, crank shaft. Hot forging experiments at 750°C are carried out on cylindrical specimens of aspect ratio 0.75 and 1.5 with true height strain (ln (ho/hf)) of 0.6. Forging load for the experiments is calculated using slab and upper bound deformation models as well as Metal forming simulation using commercially available FEA software. The upper bound models with 30% deviation from the simulation results are found to be more accurate compared to the slab models.

Any change is vehicle exterior design, affects the aerodynamics characteristic. Generally different types of roof racks are attached on passenger vehicles to carry luggage which affects aerodynamic drag. The objective of this work is to perform aerodynamic analysis of ground vehicle with roof rack to investigate the change in drag coefficient. First, the aerodynamic analysis of a baseline passenger car model is performed with and without generic benchmarked roof rack at 100 kmph. Further analysis is carried out with different new designs of roof racks. Based on simulation result, a scaled down prototype model is fabricated and validated by using a wind tunnel test for optimum suitable case. The modelling of the vehicle is done in CATIA tool and simulation is carried out by using ANSYS Fluent.

Frontal crash is the most common type of accidents in passenger vehicles which results in severe injuries or fatalities. During frontal crash, some frontal vehicle body has plastic deformation and absorbs impact energy. Hence vehicle crashworthiness is important consideration for safety aspect. The crash box is one of the most important parts in vehicle frontal structure assembly which absorb crash energy during impact. In case of frontal crash accident, crash box is expected to be collapsed by absorbing crash energy prior to the other parts so that the damage to the main cabin frame and occupant injury can be minimized. The main objective of this work is to design and optimize the crash box of passenger vehicle to enhance energy absorption. The modeling of the crash box is done in CATIA V5 and simulations are carried out by using ANSYS. The results show significant improvement in the energy absorption with new design of the crash box and it is validated experimentally on UTM.

Role of wheel and underbody aerodynamics of vehicle in the formation of drag forces is detrimental to the fuel (energy) consumption during the course of operation at high velocities. This paper deals with the CFD simulation of the flow around the wheels of a bus with different wheel housing arrangements. Based on benchmarking, a model of a bus is selected and analysis is performed. The aerodynamic drag coefficient is obtained and turbulence around wheels is observed using ANSYS Fluent CFD simulation for different combinations of wheel-housing- at the front wheels, at the rear wheels and both in the front and rear wheels. The drag force is recorded and corresponding influence on energy consumption of a bus is evaluated mathematically. A comparison is drawn between energy consumption of bus body without wheel housing and bus body with wheel housing. The result shows a significant reduction in drag coefficient and fuel consumption.

Electric passenger car with floor battery usually have its front boot space empty and the space is used as additional luggage storage. This space can be utilized to capture the wind energy and generate electricity. Based on this, the objective of this work is to perform an aerodynamic analysis of an electric passenger car using wind turbine placed at the front. Initially the aerodynamic analysis of a basic electric car model is performed and further simulated using wind turbines and aerodynamic add-on-devices. The simulation is carried-out using ANSYS Fluent tool. Based on the simulation result, scaled down optimized model is fabricated and tested in wind tunnel for validation. The result shows reduction of drag coefficient by 5.9%.

Active aerodynamics can be defined as the concept of reducing drag by making real-time changes to certain devices such that it modifies the airflow around a vehicle. Using such devices also have the added advantages of improving ergonomics and performance along with aesthetics. A significant reduction in fuel consumption can also be seen when using such devices. The objective of this work is to reduce drag acting on a passenger car using the concept of active aerodynamics with grill shutters and air dams. First, analysis has been carried out on a baseline passenger car and further simulated using active grill shutters and air dams for vehicle speed ranging from 60 kmph to 120 kmph, with each active device open from 0° to 90°. The optimized model is then validated for a scaled down prototype in a wind tunnel at 80kmph. Vehicle has been modelled using SolidWorks tool and the simulation has been carried out using ANSYS Fluent.

This paper presents a methodology for predicting thermal comfort inside Midibus cabin with an objective to modify the Heating, Ventilation and Air Conditioning (HVAC) duct design and parametric optimization in order to have improved thermal comfort of occupant. For this purpose the bus cavity is extracted from baseline CAD model including fully seated manikins with various seating positions. Solar Load has been considered in the computational model and passenger heat load is considered as per BSR/ASHRAE 55-1992R standard. CFD simulation predicted the air temperature and velocity distribution inside passenger cabin of the baseline model. The experimental measurements have been carried out as per the guidelines set in APTA-BT-RP-003-07 standard. The results obtained from CFD and Experimental test were analysed as per EVS EN ISO7730 standard and calculated occupant comfort in terms of thermal comfort parameters like Predicted Mean Vote (PMV) and Predicted Percentage Dissatisfied (PPD).

The Light commercial vehicle (LCV) is primarily used for the last mile delivery and it hold the volume share of around 61% in the commercial vehicle segment. The last mile delivery services have seen a massive surge after the CoVID 19 pandemic resulting is the increase sale of LCV in last few years and is expected to grow further by 8-11% in the coming years. However, city logistic is also responsible for most pollution and noise in the city. Hence, policymakers are aiming to reduce carbon footprint by promoting the use of Electric vehicle by providing incentive to automakers though schemes like FAME I and FAME II. In order to effectively reduce the carbon footprint within city it is important to increase the use of new electric vehicle and convert the old polluting vehicles to electric. Hence, a retro fitment solution for converting used LCV to electric can help in reducing emission as well as noise pollution. Later the same solution can be offered as OE fitment solution.