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In order to meet the challenges of future CAFE regulations & pollutant emission, vehicle fuel efficiency must be improved upon without compromising vehicle performance. Optimization of engine breathing & its impact on vehicle level fuel economy, performance needs balance between conflicting requirements of vehicle Fuel Economy, performance & drivability. In this study a Port Fuel Injection, naturally aspirated small passenger car gasoline engine was selected which was being used in a typical small passenger car. Simulation approach was used to investigate vehicle fuel economy and performance, where-in 1D CFD Engine model was used to investigate and optimize Valve train events (Intake and exhaust valve open and close timings) for best fuel economy. Engine Simulation software is physics based and uses a phenomenological approach 0-D turbulent combustion model to calculate engine performance parameters. Engine simulation model was calibrated within 95% accuracy of test data.

Recently, the Flexible Pedestrian Legform Impactor (or Flex-PLI) - an advancement over the existing EEVC legform - was included in the Global Technical Regulation for Pedestrian Safety viz. GTR-9. The legform tool undergoes impact testing with vehicle at 40kmph in order to evaluate the frontal structure of vehicle for Pedestrian Safety. Being more biofidelic design over the old EEVC legform, Flex-PLI is more flexible and sensitive towards different vehicle designs, shapes and inner bumper structure. This flexibility and sensitiveness of its design also calls for examining the Manufactured FlexPLI for its efficacy under impact testing in terms of its Durability, Repeatability and Reproducibility. This study aims at validating the performance of the test device by building a platform for computing the variations in test results. In this study, three key aspects are identified to measure the performance of this device - Durability, Repeatability, and Reproducibility.

With introduction of CAFÉ norms in India from Apr’17, the manufacturer of all M1 Category vehicles (not exceeding 3,500kg GVW) has to ascertain that they comply with Annual Corporate Average CO2 Target as defined in AIS-137 regulation which is becoming stricter in future. Hence CO2 emissions are becoming one of the major focus parameters during vehicle development. The assessment of CAFÉ compliance involves multiple steps. Firstly, test agency provides Type Approval and Conformity of Production emission test reports to the Designated Agency. Accordingly, every manufacturer submits Fuel consumption report/Passbook to the Designated Agency on annual basis. After verification of all data, the Designated Agency issues a status of compliance to the Manufacturer. Such detailed assessment protocol presents a huge challenge for any manufacturer in maintaining the consistency/accuracy of CO2 produced by manufactured vehicles within the Type Approved Limit.

The most widely used type of windshield wiper system employs a coil spring for wiper arm pressure generation. This spring is fixed between the arm head (fixed part) and wiper arm (moving part) and the tension in the spring is responsible for pressure generation. The present arrangement although being unsophisticated design, has following drawbacks: Inability to change wiper arm pressure according to change in vehicle speed. Inability to provide constant arm pressure during the complete range of motion along varying curvature of windshield. Inability to reduce/remove the continuous pressure on wiper blade when vehicle is parked for long durations resulting in permanent deformation of wiper blade rubber. This paper describes how electromagnets can be used to overcome the above stated inherent limitations of the windshield wiper system. An electromagnet is a device which produces magnetic field on application of electric current.

Road Load parameters (rolling resistance and aerodynamic drag) of a vehicle have strong impact on overall Vehicle Emissions and Fuel Economy. The road load coefficients are simulated on chassis dynamometer to carryout emission and fuel economy measurement and are hence required to be found beforehand. A realistic measure of road load parameters can be obtained by conducting a coastdown test. Coastdown test results are hugely impacted by various environmental parameters like ambient temperature, atmospheric pressure, wind speed etc. Though performed in standard boundary conditions, results of multiple tests performed on a vehicle vary from one another due to variations in the mentioned environmental parameters over and above standard test to test variation. This paper aims at studying the variation in test results due to ambient temperature as one of the parameters responsible.

Gearbox power transfer efficiency is a major factor in overall powertrain efficiency of a passenger vehicle. With rapidly changing emission and fuel efficiency regulations, there is a push to increase the gearbox efficiency to improve the overall fuel economy of the vehicle. In case of an existing gearbox, efficiency can be improved by using the low viscosity lubrication oil. Despite a benefit in increasing the gearbox efficiency, lowering down the viscosity of lubrication oil gives rise to few challenges with respect to its performance. One of these challenges is breather performance which defines that transmission oil should not come out of breather pipe in some pre-defined conditions during gearbox operation. As this validation is being carried out on proto parts when the complete system is ready, failure to satisfy the defined criteria for breather performance can lead to multiple trials.

Front suspension frame is an integral part of automobile chassis which acts as a major load carrying structural member and connects different suspension components with body. It provides the required stiffness for achieving desired vehicle dynamics performance. Acting as a major road load path from tire to body, it also acts as a mounting base for suspension arm, steering and compression rod. Considering the competitive market conditions, increased fuel efficiency demand along with enhanced structural durability, it is important to evaluate suspension frame for stiffness and durability using Computer Aided Engineering (CAE) methodology so as to reduce product development time and First Time Right cost effective design. In this paper focus is given on CAE methodology used to design a light weight tubular kind of suspension frame for light commercial vehicle with stiffness comparable to conventional sheet metal suspension frame and similar durability performance with reduced weight.

In today’s Indian automotive industry, vehicles are becoming more complex and require more efforts to develop. Also, new and upcoming regulations demand more trials under varied driving conditions to ensuring robustness of emission control. Combined with expectations of customer to get new products more frequently, requires solutions and methods that can allow more trials with required accuracy to ensure compliance to stricter regulation and delivery a quality product. This translates into more trials in less time during the development life cycle. Recently, to overcome above challenge, there has been focus on simulating the vehicles trials in engine bench environment. ‘Road to Lab to Math’ (RLM) is a methodology to reduce the effort of On-road testing and replace it with laboratory testing and mathematical models. Also, on-road testing of prototype vehicles is expensive as it requires physical parts.

The field of Passive Safety is of primary focus for the automobile manufacturers. Number of changes has been incorporated in today’s passenger car, which not only protects its occupants but also other road users. This revolutionary change in technology calls for new development in evaluation procedures. Crash testing of vehicles is one such massive field of research. The nature and cost of these tests increases the need for better measurement techniques. High speed cameras are often used in the crash tests and image processing is done to study the deformation characteristics, dummy kinematics and steering wheel displacements. This paper discusses the effect of key factors like Camera positioning and 2D Calibration on the analysis of high speed images. The paper also discusses the experimental evaluation carried out to validate the same.

Energy dissipation testing of vehicle's interior fitments is done at various defined locations as per the regulation ECE R21. Interior fitting impact tests became mandatory in April 2006 for models manufactured from April 2006 and April 2007 for models being manufactured before April 2006 in India. With the implementation of stringent safety regulations in India, it is mandatory that every manufacturer tests and certifies their product to comply with the automotive safety standards. Automotive industry has a challenging task of designing and evaluating the components that play a vital role in the event of an unfortunate accident. In this context, a number of tests on safety belt anchorages, seat anchorages and interior fittings such as instrument panel, steering wheel etc., are conducted.

The fuel efficiency of a vehicle depends on multiple factors such as engine efficiency, type of fuel, aerodynamic drag, and tire friction and vehicle weight. Analysis of weight and functionality was done, to develop a lightweight and low-cost Roof rack rail. The Roof rack rail is made up of a lightweight material with thin cross section and has the design that allows the fitment of luggage carrier or luggage rack on the car roof. In starting this paper describes the design and weight contribution by standard Roof rack rail and its related parts. Secondly, the selection of material within different proposed options studied and a comparison of manufacturing and design-related factors. Thirdly, it has a description of the design of Roof rack rail to accommodate the luggage carrier fitment on the car roof. Moreover, optimizations of Roof rack rail design by continuous change in position, shape, and parts used.

Vehicle Hood being the face of a passenger car poses the challenge to meet the regulatory and aesthetic requirements. Urge to make a saleable product makes aesthetics a primary condition. This eventually makes the role of structure optimization much more important. Pedestrian protection- a recent development in the Indian automotive industry, known for dynamics of cost competitive cars, has posed the challenge to make passenger cars meeting the regulation at minimal cost. The paper demonstrates structure optimization of hood and design of peripheral parts for meeting pedestrian protection performance keeping the focus on low cost of ownership. The paper discusses development of an in-house methodology for meeting Headform compliance of a flagship model of Maruti Suzuki India Ltd., providing detailed analysis of the procedure followed from introduction stage of regulatory requirement in the project to final validation of the engineering intent.

Valve train system is one major contributor to engine overall friction loss and is approximately 30% of total engine friction at lower speed and approximately 20 % at higher engine speed. Valve spring loads (preload and working) are proportional to friction loss of valve train. To optimizing the valve spring design main requirement is valve train perform it function safely at maximum engine cutoff RPM with minimum preload and working load. Robustness and frictional power loss are contradicting requirement, robustness demand high stiffness spring for better valve jump and bounce performance with dynamic safe valve spring design, on the other hand low frictional power loss demand for use of low stiffness spring. To optimize the valve spring stiffness for meeting both the requirement we need accurate prediction of valve spring in design stage and good correlation with testing data to reduce the number of iterations.

Fun to drive, pick-up of vehicle, high acceleration feeling of vehicle, time to reach max velocities are some parameters prevailing in the passenger vehicle market. In addition to focusing on information about fuel economy declared by manufacturer, the customer also has drivability related criteria in his mind. Although drivability is subjective, it can be judged by using various parameters like maximum speed, pick-up feeling, overtaking acceleration, time to reach 0 – 100 km/h or 0 – 60 km/h, etc. While comparing two vehicles of the same segment, one vehicle may perform better on some of the parameters while losses on others. To decide overall drive performance of a vehicle based on various measured performance related parameters, a methodology is defined. This will help to understand the overall performance of a vehicle holistically and to compare its performance with other vehicles in a better way.

In view of global concern for greenhouse gas emissions, need for greener and efficient Engines is increasing. Hence is it imperative that Internal Combustion Engines are improved in terms of efficiency to reduce Greenhouse gas emissions and meet CAFE targets. The cooling system of an ICE plays a major role in a vehicle performance. In this system, the radiator, thermostat, and cooling fan are the main components. Conventional cooling system uses Wax-type thermostat which is activated at specified coolant temperature and maintain same coolant temperature in fully warmed up condition at all engine operating points. Operative temperature selection in Wax-type is trade-off between engine friction & thermal efficiency at lower loads & knocking at higher loads. An electronic thermostat is a good alternative to maintain optimum temperature as per operating point requirement since optimum temperature at different operating points can be different.

Presently, lot of research is going on, to improve the thermal efficiency and there by the Fuel Economy of vehicles. Increasing the compression ratio to improve on the performance is an option. The compression ratio is a factor that influences the performance characteristics and FE of internal combustion engines. When targeting high output levels at low engine speeds, undesired combustion events called pre-ignition can occur. These pre-ignition events are typically accompanied by very high cylinder peak pressures which can lead to severe damage of engine component. The application engineer needs to optimize this undesired combustion event. This paper describes a systematic application developed to reduce pre-ignition. A case study was done to identify the pre-ignition phenomenon by using in-cylinder measurement. The paper also explains how air, fuel, injection angle and spark can help to avoid pre-ignition.

Hood is the closure provided in the frontal portion of the vehicle for covering the engine room. Any component disposed in the frontal portion of the vehicle becomes important because of aesthetic as well as regulatory requirements. Introduction of new regulations like pedestrian protection brings new challenges for the original equipment manufacturers and the governing authorities. Introduction of Pedestrian Protection regulation, a recent development in the automotive industry, has thrown several questions in front of original equipment manufacturers. This work explains the procedure to address such question and the learning associated with it.

In a typical passenger vehicle, there can be different types of noises generated which are broadly categorized as Interior Noise and Exterior Noise. The interior noise sources can be further classified into noises which can be Structure Borne or Air Borne. One of the major sources of both structure borne and airborne noise generation is the powertrain of the vehicle. The structure-borne noise and vibrations generated from the powertrain is usually transferred to the vehicle body through its attachment points to the body and the powertrain driveline. These induced body vibrations can sometimes cause the acoustic cavity of the passenger cabin to go into resonance which results in an annoying and disturbing noise for the passengers, called Booming Noise. Very often, one or more than one vehicle body panels show a dominant contribution in inducing this acoustic cavity resonance.

With the change in the perspective of the Customers towards safer vehicles, most of the Vehicle manufacturers in India are making their vehicles Crash compliant. According to the accidental data collection, Side crashes are second leading cause of death after Frontal crash. Currently sub system level tests are done for evaluating the side impact safety performance of the vehicle. One of such sub system level test is Quasi-static side door intrusion Test. The primary purpose of this testing is to measure the Force-deflection characteristics by intrusion of the impactor into the vehicle. These characteristics are controlled by various door components like door beam, latch & striker, hinge etc. This article studies the relation between Side door intrusion and Side collision, effect of above mentioned components on this relation. A theoretical study is done to study this relationship and it is substantiated with experimental data.

BIW (Body-in White) is a type of vehicle structure formed by spot welding of different sheet metal components. The BIW structure should be designed to support the maximum load potential under various performance conditions. Thus the structure should have good strength as well as stiffness. Torsion Stiffness of BIW is the amount of torque required to cause a unit degree of twist. It is often considered as a benchmark of its structural competence due to its effect on various parameters like ride, handling, lateral load distribution and NVH performance of vehicle. The paper aims to design and develop a test methodology and test fixtures for measuring the BIW torsion stiffness with repeatability of test results and also have an (R2>0.99) for the measured values in the test.