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Electric vehicles have a limitation of limited range and long charging time. Energy optimization plays a very crucial role in determining the range of an electric vehicle. The innovative system proposed here gives the opportunity to reduce energy wastage and efficiently direct the electrical energy to improve the driving range of a 9 meter AC electric bus. The high voltage air conditioner unit alone consumes more than 40% of the electrical energy stored in the traction battery which reduces the driving range of the electric bus drastically. The proposed system optimizes the air conditioner utilization to direct cool air only in areas where passengers are present. Buses do not always run on full capacity, when there are less number of people in the bus the system detects the locations of the passengers using sensors and occupant detection algorithm, this enables the controller to identify the areas where cooling has to be focused and where cooling can be reduced or stopped.

Passenger vehicles are used as one of the frequently used and versatile mode of transport. Commercial buses cater to short to long distance travel for city as well as highway applications. Thus, passenger ride comfort becomes paramount for the salability of the vehicle. Generally, it is observed that the rear seat experiences the worst ride comfort characteristics due to rear overhang and pitching characteristics of buses. Therefore the objective of this project is to improve the rear seat vibrations of passenger bus by tuning damper characteristics. Shock absorbers, being a low cost and easily interchangeable component is tuned first before optimizing other suspension parameters. The methodology is as follows: first, a 4 degree of freedom mathematical model is created on MATLAB Simulink R2015a environment. Time domain data is obtained by road load data analysis and used as an input for the mathematical model.

In cylinder combustion and emission characteristics are dependent on piston bowl geometry design. In-cylinder fuel air mixing and flame front movement are influenced by piston bowl shape and design. These phenomena in turns affect the combustion behavior and the power developed by the diesel engine. In this study piston bowl geometry optimization of a LMD diesel engine is carried out to improve the torque and BSFC output at low end rated operating zones. The optimized bowl geometry is also incorporated in the engine and validated on the test bed. In this work, a commercially available CFD code AVL FIRE is used for combustion simulation and bowl geometry optimization. The validation of in-cylinder combustion simulation of a 2 liter Turbocharged LMD BS-VI diesel engine with base piston bowl geometry is carried out with the available test data.

In the current commercial vehicles market, ride-comfort and handling are crucial parameters for the customer and end user. There are various aspects which determine the vehicle behavior. One of aspects is the structural rigidity of the vehicle, which has its own effect on vehicle dynamics. To meet the required stiffness of the main structural component of the vehicle i.e. chassis frame, FEA analysis has to be done in current methodology. The number of iterations have to be done to build an appropriate model with low weight, which can meet the design requirements. At first, conceptual design mock-up unit is to be developed then FEA (CAE) analysis to be done on it. If any design criteria are not met, then this cycle repeats again until it fulfils the required stiffness. Today, the direct stiffness procedure is the basic principle of almost every FEA software package.

Chassis frame of a passenger vehicle is one of the primary load bearing components of the vehicle. All the aggregates such as engine, radiator, fuel tank, EATS, air tanks, body and cowl etc. are mounted on to the frame. It should have sufficient stiffness and strength to withstand the static and dynamic loads. At the same time it should also be light in weight as it helps in reducing the fuel consumption and emissions coming out of the vehicle. The main objective of this work is to design a chassis frame of a passenger vehicle of M3 category using Design of Experiments by considering the stiffness and the natural frequency of a similar type of vehicle’s frame (Benchmark) as the target values i.e. the final design of the frame should match the stiffness and natural frequency values of the benchmarked frame with a specified tolerance set as per the general methodology of frame design.

The Mounting system of component plays a major role in determining the structural durability, compatibility and synchronization of the systems with respect to each other. The major function of Engine mounts is to isolate the engine from the chassis and to align the power-train system of vehicle according to needs. Here we exclusively deal with the failure case of a Heavy duty commercial vehicle Engine Mounts and its optimization. We do formulate a theoretical calculation for the estimation of engine loads, Center of Gravity (C.G) and characteristics of existing engine mount followed by a failure root cause analysis based on design and transmissibility parameters. This is then correlated with data from Computed Aided Engineering and Matlab for analysis of the existing model which is compared to the experimental transmissibility from Road load data Acquisition (RLDA). This is to validate the conditions and propose optimizations to reduce critical failures.

Tractor-semitrailers make up large proportion of heavy commercial vehicles, handling stability of tractor-semitrailers is critical to driving safety. Handling behavior of Tractor-semitrailers is complex and depends on various parameters. This paper presents a mathematical approach & multi body dynamics (MBD) simulation based study to gain an insight as to, how changes to different parameters of the articulated vehicle affect it’s handling behavior and thus to obtain an optimized design in terms of vehicle handling. A Full vehicle multi body dynamic model is created and steady state cornering maneuvers are performed on simulation tool MSC ADAMS/View for calculating understeer gradient using constant radius test method. Various parameters affecting understeer gradient are identified, studied and their relative effect on understeer gradient is measured. These critical parameters were then optimized using MSC ADAMS/View tool to achieve the desired handling targets.

To compete with the current market trends, there is always a need to develop cost effective frame designs to meet the needs of the customer. During the development of new vehicles, the major focus is on weight reduction, so as to improve the load carrying capacity and fuel efficiency. Due to the introduction of new high strength materials, the static strength conditions can be met by the use of thinner frames, but the dynamic behavior of the frame deteriorates. The dynamic behaviors like ride and handling, comfort are affected by the stiffness of the vehicle frame. The stiffness of the frame is majorly defined by its vertical stiffness, lateral stiffness and torsional stiffness. The vertical stiffness of the frame plays major role in isolating road vibrations to frame mounted aggregates. The lateral stiffness plays a very important role in the handling of the vehicle and cornering ability of the vehicle. Torsional stiffness effects the roll and lateral load transfer distribution.

An efficient after treatment technique is driven by the need to maintain strict emission norms for heavy-duty and medium-duty ground vehicles. SCR being an advanced active emission technology system for diesel engine, is one of the most cost-effective and fuel-efficient technologies available for complying with the stringent NOx emission legislations. The design of the SCR system involves catalyst selection, complex controller development like urea dosing strategy and the interaction between engine setup and after treatment system. For this purpose, the SCR model must be computationally efficient to evaluate the complete efficiency along with to take care for the NH3 slip also. The SCR model was prepared with respect to SCR inlet temperature and ratio of NOx and ammonia to study the behavior of NOx conversion efficiency keeping consideration of NH3 slip also required for optimizing the calibration.

The need to develop products faster and to have designs which are first time right have put enormous pressure on the product development timelines, thus making computer aided optimization one of the most important tool in achieving these targets. In this paper, a design of experiments (DOE) study is used, to gain an insight as to, how changes to different parameters of front suspension and steering of a passenger bus affect its kinematic properties and thus to obtain an optimized design in terms of handling parameters such as bump steer, percent ackermann error and lock to lock rotation angle of steering wheel. The conventional hit and trial method is time consuming and monotonous and still is an approximate method, whereas in design of experiments (DOE), a model is repeatedly run through simulations in a single setup, for various combinations of parameter settings.