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This paper discusses the methodology setup for grill opening area prediction at the early development phase of the product development lifecycle, using a commercially available 1D simulation tool- AMESIM. Representative under hood has been modeled using Grill, Condenser, Radiator, intercooler, fan, and engine components. Vehicle velocity is used as an input to derive the airflow passing through the grill and other under-hood components based on ram air coefficient, pressure drop through different components (Grill, Heat exchanger, Fan & Engine). This airflow is used to predict the top tank temperature of the radiator. Derived airflow is correlated with airflow obtained from CFD simulation. A balance has been achieved between cooling drag & fan power consumption at different grill opening areas for target top tank temperature. Top tank temperature has been predicted at two different extreme engine heat rejection operating points.

In present study a comparative investigation and correlation attempted on small scale vehicle model for aerody-namic drag performance at small scale wind tunnel test facility in India vs full vehicle tested at globally know and accepted full scale test facility in Pininfarina, Italy. Current investigation aims to assess the small-scale wind tunnel suitable for testing 1:3 small scale car models A scale model of 1:3 scale size was tested in small scale wind tunnel (at IISC,Bengaluru, India) having test section area of 11.68 Sq. m. To understand the overall vehicle aerodynamic drag performance small scale model was test-ed for different configurations such as baseline, spoiler removal, underbody cover and different yaw condition. To understand the correlation between small scale vs full vehicle’s aerodynamic performance one actual vehicle was also tested at full scale wind tunnel Pinifarina Italy.

Original Equipment Manufacturers (OEMs) should innovate ways to delight customers by creating affordable products with improved drive experience and occupant comfort. Vehicle refinement is an important initiative that is often take-up by the project teams to ensure that the product meets the customer’s expectations. A few important aspects of vehicle refinement include improving the Noise Vibration Harshness (NVH), ride and handling performance pertaining to the Functional Image (FI) of the product. Optimizing the suspension design variables to meet both ride and handling performance is often challenging as improving the ride will have a deteriorating effect on handling and vice-versa. The present work involves Multi-Objective Design Optimization (MDO) of the suspension system of an automotive Sports Utility Vehicle (SUV) platform considering both ride and handling requirements, simultaneously.

The increasing demand for higher specific power and the need for weight reduction and decrease of emissions have become the driving factors of product development in the automotive market today. Substitution of high-density materials and more precise adjustment of material parameters help in significant weight decrease, but it is accompanied by undesirable cost increase and manufacturing complexity. One of the approaches to optimize the design is through the process of integration which involves integrating the functional elements of two or more components into one and achieving a reduction in weight and cost without impacting required performance. This paper explains a similar approach followed as a part of the Design and Development of 1.5 L, 3 Cylinder CRDI Diesel Engine for a new vehicle platform, developed for automotive passenger car application.

The automobile industry strives to develop high-quality vehicles quickly that fulfill the buyer’s needs and stand out within the competition. Full utilization of simulation and Computer-Aided Engineering (CAE) tools can empower quick assessment of different vehicle concepts and setups without building physical models. Vehicle execution assessment is critical in the vehicle development process, requiring exact vehicle steering system models. The effect of steering system stiffness is vital for vehicle handling, stability, and steering performance studies. The overall steering stiffness is usually not modeled accurately. Usually, torsion bar stiffness alone is considered in the modeling. The modeling of overall steering stiffness along with torsion bar stiffness is studied in this paper. Another major contributing factor to steering performance is steering friction. The steering friction is also often not considered properly.

Parametric model of a production hybrid (made up of reactive and dissipative elements) muffler for tractor engine is developed to compute the acoustic Transmission Loss (TL). The objective is to simplify complex muffler acoustic simulations without any loss of accuracy, robustness and usability so that it is accessible to all product development engineers and designers. The parametric model is a 3D Finite Element Method (FEM) based built in COMSOL model builder which is then converted into a user-friendly application (App) using COMSOL App builder. The uniqueness of the App lies in its ability to handle not only wide range of parametric variations but also variations in the physics and boundary conditions. This enables designers to explore various design options in the early design phase without the need to have deep expertise in a specific simulation tool nor in numerical acoustic modeling.

In automotive door engineering, fitting the side door glass surface from styling into the cylinder or torus is the basic requirement. Optimization is required to do this, which requires a solver which could be efficacious for best surface fitting. This paper propounds a methodology which could be used for fitting a side door glass surface from styling into the cylinder or torus. The method will significantly help in developing the required surface and can successfully eliminate the cumbersome manual calibrations. The mathematical model mentioned is a novel approach based on “Particle Swarm Optimization” (“PSO” will be used to represent in the paper) towards surface optimization technique. VB script is used to make it applicable in CATIA but could be easily applied in any other programming language like python, java etc. Usually the surface fitting problems deals with the initial guess of the required surface and then its further optimization.

Accurate ride and handling prediction is an important requirement in today's automobile industry. To achieve the same, it is imperative to have a good estimation of damper model. Conventional methods used for modelling complex vehicle components (like bushings and dampers) are often inadequate to represent behaviour over wide frequency ranges and/or different amplitudes. This is difficult in the part of OEMs to model the physics-based model as the damper’s geometry, material and characteristics property is proprietary to part manufacturer. This is also usually difficult to obtain as a typical data acquisition exercise takes lots of time, cost, and effort. This paper aims to address this problem by predicting the damper force accurately at different velocity/ frequency and amplitude of measured data using Artificial Neural Networks (ANN).

Aerodynamics of on-road vehicles has come to the limelight in the recent years. Better aerodynamic design of vehicle would improve vehicle fuel efficiency with increased acceleration performance. To obtain best aerodynamic body, the series of design modifications and different testing methodologies must be involved in vehicle design and validation phase. Wind tunnel aerodynamic force measurement, road load determination and computational fluid dynamics were the common methods used to evaluate the aerodynamic behavior of the vehicle body. As a novel approach, the present work discusses about the on-road (Real time) testing methodology that is aimed to evaluate the aerodynamic performance of vehicle body using surface pressure mapping. A 64-Channel digital pressure scanner has been utilized in this work for mapping the pressure at different locations of the typical vehicle body.

Melatonin, otherwise popularly known as the “sleep hormone” is known to govern the human circadian rhythms. Current studies indicate that the generation of melatonin is impacted by the ambient light. The natural sleep inducing behavior during night and in darkness, is also due to the same phenomenon. Studies have shown that light of particular wavelengths in the visible spectrum have a higher effect on the amount of melatonin secreted by the human body. Blue light in the wavelengths of around 468 nm is known to inhibit the melatonin secretion, the most. This branch of science known as photobiology is in its nascent stage and is a matter of research pursued by neurologists, endocrinologists and other lighting researchers. Photobiology has several potential applications in the automotive industry, the principal one being driver drowsiness prevention.

It is imperative that all automobile manufacturers conduct vehicle level benchmarking at the initial stage of any new project. From the benchmark information, the manufacturers can set relevant targets for their own vehicles under development. In this regard, an accurate prediction of the engine operating points can improve the correlation of the measured fuel economy of the benchmark vehicle. The present work describes a novel method that can be used for the accurate prediction of the engine operating points of any benchmark vehicle. Since the idea of instrumenting the crankshaft/driveshaft with torque transducers is a costlier and time-consuming process, the proposed method can be effective in reducing the benchmarking. Hence, the objective of this work is to develop a mathematical model to calculate the real-time engine operating points (engine speed and torque) using parameters like vehicle speed, accelerator pedal map, driveline inertia, vehicle coastdown force and gradient.

In the automotive industry the requirement for low emissions has led to the demand for lightweight vehicle structures. Light weighting can be achieved through different iterative approaches but is usually time consuming. Current paper highlights deployment of the multi-loadcase optimization approach for light weighting. This work involves developing a process for multiple loadcase optimization for automotive hood. The main goal is to minimize the weight of a hood assembly by meeting strength and stiffness targets. The design variables considered in this study are thickness of the panels. Design constraints were set for stress and stiffness based on DVP (Design Verification Plan) requirement. Optimization workflow is setup in mode-frontier with design objective of minimizing weight of hood.

Canopy design is governed by CPCB regulations. The regulations explicitly tells about noise levels. It’s very important to have the proper ventilation of canopy to ensure the proper working at all climatic conditions. Mostly it is installed at commercial locations & hence the ownership cost matters. Reducing the footprint without affecting the power output is challenging. It implies the need of the CFD simulation to predict the cooling performance of the canopy. The baseline canopy is tested to estimate the performance parameters. It is modelled in CFD with all the minute details. All the parts including engine, alternator, fan, fuel tank are modelled. MRF(Moving Reference Frame) model used to simulate fan performance. The cooling systems like radiator & oil cooler is modelled as porous region. The total flow across canopy & the air velocity across critical regions is used to define the performance.

One of the primary excitation sources in a passenger car comes from the powertrain [1]. Refinement of powertrain induced noise is the most critical tasks during a vehicle refinement. Due to ever increasing demand for reduced design and development cycle, most critical decisions have to be made at the concept stage. Powertrain radiated noise is one of the most important performance factor that must be evaluated during the concept stage. Solution time for calculating the radiated noise using the existing acoustic solvers is very high and requires very expensive resources like software and hardware. Arriving the optimal design with conventional method is very tedious job. A new method has been adopted for identifying the critical areas and coming up with the optimal design modifications within a short span of time. Powertrain radiated noise has been calculated with the help of acoustic solver.

The global automotive industry is growing rapidly in recent years and the market competition has increased drastically. There is a high demand for passenger car segment vehicles with high torque delivery and fuel economy for a pleasant drivability experience. Also, to meet the more stringent emission requirements, automakers are trying very hard to reduce the overall vehicle gross weight. In lowering both fuel consumption and CO2 generation, serious efforts have been made to reduce the overall engine weight. An engine cylinder block is generally considered to be the heaviest part within a complete engine and block alone accounts for 3-4% of the total weight of the average vehicle, thus playing a key role in weight reduction consideration. Aluminum casting alloys as a substitute for the traditional cast iron can mean a reduction in engine block weight between 40 and 55% [9], even if the lower strength of aluminum compared to grey cast iron is considered.

Currently the Automotive industry demands highly competitive product to survive in the global tough competition. Even if there is a slight reduction in product cost and time has a high significant impact on business. Engineers are under tremendous pressure to develop competitive and give better product concern resolution at the earliest. To arrest the failure of this thermostat vent, an innovative approach was used to relocate de-aeration restrictor on the hose to the thermostat root. Thus, resolving the product concern by increasing the strength of the vent at root and providing good business impact on cost savings. Physical testing has provided an effective way to smoothen product development for concern resolution. This Paper highlights approach on an attempt to field failure simulation with existing and modified design with lab test results.

The ECE R-14, AIS015 safety standard specifies the requirements of the safety belt anchorages namely, minimum numbers, their locations, static strength to reduce the possibility of their failure during accidental crashes for effective occupant restraint and the test procedures. This standard applies to the anchorages of safety belts for adult occupants of forward facing or rearward facing seats in vehicles of categories M and N. ECE R14 ensures the passenger safety during sudden acceleration/retardation and accidents. Early simulations revealed some structural short falls that demanded cabin improvements in order to fulfill regulation requirements for the seal belt anchorage test. This paper describes the innovative design modifications done to meet the seat belt anchorage test. Good correlation with the test is achieved in terms of deformations. These simulation methods helped in reducing the number of intermediate physical tests during the design process.

With increasing road traffic and pollution, it becomes responsibility for all OEM to increase fuel efficiency and reduce carbon footprint. Most effective way to do so is to reduce weight of the vehicle and more use of ecofriendly recyclable material. With this objective we have come up with Light weight, cost effective sustainable design solution for Injection moulded RQT (Rear quarter trim). It is an interior plastic component mounted in the III row of the vehicle. This is required to ensure inside enhanced aesthetic look of the vehicle and comfort for 3rd row passengers. Conventionally RQT of vehicle with 3rd row seating is made using plastic material (PP TD 20). With the use of plastic moulded RQT there is a significant weight addition of around 6 kg per vehicle along with reduced cabin space, huge investment and development time impact.

Gear rattle is an annoying noise phenomena of the automotive transmission, which is mainly induced by torsional fluctuation of engine. In this study, torsional vibration of 3 cylinder powertrain is analyzed and improved for reducing the gear rattle from transmission by using parametric optimization. One dimensional Multi-body mathematical model for the torsional vibrations of front wheel drive automotive drivetrain is developed and utilized for the optimization of sensitive parameters of the driveline. Second order differential equations of the mathematical model are solved by using MATLAB and the output response is validated with the test data. Parametric optimization is conducted by using design of experiment method. The updated model is further utilized for optimizing the flywheel inertia, driveshaft stiffness and clutch stiffness. Mathematical modelling and optimization process has helped to achieve NVH targets for driveline.

Primary function of a drive half shaft is to transfer torque from transaxle to the wheels in East West configuration powertrain vehicles. Conventional practice is to consider either 1st gear max torque or the Wheel slip torque, whichever being the maximum as design torque. However vehicle dynamics and Powertrain characteristics have a major influence on the Driveshaft torque and the torques experienced can thus go beyond the design torque. This questions the design endurance limit for the driveshaft based on conventional design. One such situation is the torque experienced by the driveshaft during vehicle coasting condition with gear downshift. The torque experienced in such a scenario can go beyond the maximum design torque leading to failure as was observed in Vehicle level validation test.