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A numerical method for generating a blockloading profile from a rainflow histogram is described. Unlike previous techniques, this method produces a blockloading profile which, when rainflow-counted, yields a rainflow histogram identical to the original. When implemented with modern data acquisition and signal-processing techniques, this generation method provides a means of developing blockloading test profiles which are correlated with actual service data. This key benefit elevates existing simple testing systems as useful and productive tools despite the emrgence of more complex testing systems.

Product development processes generate large quantities of experimental and analytical data. The data evaluation process is usually quite lengthy since the data needs to be extracted from a large number of individual output files and arranged in suitable formats before they can be compared. When the data quantity grows extremely large, manual extraction cannot be done in a limited timeframe. This paper describes a set of tools developed by MTS engineers to automatically extract the desired information from a large number of files and perform data post-processing. The tools greatly improved both speed and accuracy of the evaluation process during the development of a sound quality-based end-of-line inspection system for seat tracks [1]. It allowed engineers to quickly gather a comprehensive understanding of the relative importance of individual design parameters and of their correlation to the subjective perception of the sound quality of the seat track.

In recent studies, the health implications of ultra fine particle emissions from vehicles have been investigated in a number of international studies. The adverse health effects are not only dependent on total particulate mass but also on other attributes including size, number and surface area of the particles. These ultra fine particles cause more adverse effect than larger particles. With this need UNECE GRPE had launched a Particulate Measurement Program (PMP) to formulate the regulation to control both particulate mass and number of ultra fine particles. These new regulations are applicable to the diesel and gasoline direct injection passenger cars and heavy duty engines of Euro-V/VI technology. However, at present the other vehicle categories and alternate fuels are not been covered. Limited experiments have been carried-out on the in-use vehicles which are with old technologies.

Environmental pollution is of great concern; hence the emission norms for the diesel engines are made more stringent. The purpose of this work is to develop a process to optimize the FIS parameters and select a most suitable FIS by simulation to meet the target emissions. During the combustion optimization exercise of diesel engine, different hardware combinations like injector, HPP etc are matched through testing to achieve the required performance and emissions. The process requires the real testing of the engine on engine dynamometer with various hardware combinations, which is expensive and time consuming. A simulation model of diesel FIS is constructed using ‘AVL Hydsim’. The model is validated by comparing the predicted and the experimental results. The validated model is used for further work. Critical parameters were listed based on the sensitivity analysis on the base model.

Anthropometric data of a country is vital database for automotive design and other design applications. It is also an important parameter in population studies. Most developed countries have invested resources over the years to develop such a database and this information is accessed by many OEMs and major Design Houses. However, an updated and comprehensive Anthropometry of Indian Population is largely unknown. In the past, a few institutions have done projects to bring out a picture of the Indian Anthropometry. However, keeping in view the rapid industrialization and increase of India-specific designs which require an access to latest Anthropometric database, the project “SIZE INDIA” has been initiated. For the first time in India, a state of the art 3D Whole body scanner technology has been used and thereby large volume of data has been generated in a very short span of time.

Recently, the use of laboratory-based physical prototype testing as well as the design of virtual models and virtual test equipment has accelerated the pace and quality of racing vehicle development. In particular, the combined use of both virtual and physical testing, when correlated to racetrack improvements, yields a powerful development tool(1), (2),(3). In this study, we applied these techniques from the first stages of the design of a unique Grand Prix racing motorcycle. First, a wire-frame CAD model, then a parametric CAD solid model of the motorcycle was created after preliminary calculations specified the approximate design of structural elements. Subsequently, a virtual dynamic model was created and subjected to a variety of inputs, including sine sweeps, shaped white noise and simulated road time-histories. Loads and other dynamic responses were measured on the virtual model, so that it's design could then be optimized to yield acceptable performance and durability.

Exhaust noise is the major noise source for the automotive vehicle contributing to its interior as well as exterior noise. The Transmission Loss (TL), noise reduction, Insertion Loss (IL) and radiated noise are the major characteristics used to describe the performance of a muffler in an automotive exhaust system. Out of these characteristics, Insertion loss and exhaust radiated sound pressure levels plays a significant role in muffler design as it is a measure of true performance of muffler along with engine/vehicle and very much useful for the designers to compare different silencer configurations. In present work, the sound source is modelled by acoustic impedance and volume velocity of the engine. Since it is difficult to estimate the sound source impedance of the exhaust by measurements either with direct or indirect methods as both are prone to errors and difficult to implement, the empirical equations are used to define exhaust source, to have reasonable accuracy.

5 belt wind tunnels are the most common facility to conduct the experimental aerodynamics development for production cars. Among aerodynamic properties, usually drag is the most important development target, but lift force and its front/rear balance is also important for vehicle dynamics. Related to the lift measurement, it is known that the “pad correction”, the correction in the lift measurement values for the undesirable aerodynamic force acting on wheel belt surface around the tire contact patch, must be accounted. Due to the pad correction measurement difficulties, it is common to simply subtract a fixed amount of lift values from measured lift force. However, this method is obviously not perfect as the pad corrections are different for differing vehicle body shapes, aerodynamic configurations, tire sizes and shapes.

The purpose of this paper is to present the past and present concepts of mechanical test optimization, which means the adjustment of a test machine command signal to achieve desired amplitude and mean levels. In particular, the methods of null pacing, dynamic frequency control, classical amplitude control, and maximum velocity limiting / control are discussed along with their respective application areas, advantages and disadvantages. Also, the factors of data verification and over-complication of the test are noted.

Rapid development of advanced multi-axial load transducer systems now requires the use of computer-based analytical tools to assist the development engineer optimize the design to meet often-conflicting design targets. This paper presents a case study based on the development of a wheel force load transducer to meet a challenging set of performance goals including accuracy, repeatability, durability and insensitivity to the external environment. The paper also highlights the limitations of some of the current analytical tools when used for load transducer design, and how these limitations can be overcome by cost-effective combinations of analytical performance prediction and physical test confirmation.

New process development of forging component require lot of process knowledge and experience. Even lots of trial-and-error methods need to be used to arrive at optimum process and initial billet dimensions. But with help of reliable computer simulation tools, now it is possible to optimize the complete process and billet dimensions without a single forging trial. This saves lot of time, energy and money. Additionally, simulation gives much more insight about the process and possible forging defects. In this paper, a complete forging process was needed to be designed for a complex component. With the help of computer simulation, the complete conventional forging process and modified forging process were simulated and optimized. Forging defects were removed during optimization of the process. Also billet weight optimization was carried out. Deciding the pre-forming shape of the billet was the main challenge.

Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. DI diesel engines with four valves per cylinder are widely used in off- highway applications because of the fundamental advantages of higher volumetric efficiency, lower pumping loss, symmetric fuel spray & distribution in combination with the symmetric air motion which can give nearly optimal mixture formation and combustion process. As a result, the fuel consumption, smoke levels and exhaust emissions can be considerably reduced. In particular, the four-valve technology, coupled with mechanical low pressure and electronic high pressure fuel delivery systems set different requirements for inlet port performance. In the present paper four valve intake port design strategies are analysed for off highway engine using mechanical fuel injection systems.

An analytical approach to developing motorcycle suspensions is presented. Typical uncontrolled and subjective evaluations that place limits on suspension development are curtailed through the use of a laboratory-based road simulation technique, which evaluates vehicle ride quality. Ride comfort is calculated using a specifically tailored NASA model after primary and secondary frequency regimes have been established for this type of motorcycle. Correlation between road and laboratory simulation is measured and compared to the road data variance. A designed experiment evaluates changes in ride quality as a function of suspension and tire pressure adjustments. Various suspension settings are repeated on the simulator and corresponding ride numbers are calculated for both environments. An analysis is performed to correlate ride quality improvements on the simulator with ride quality improvements in the field.

The exhaust emission legislation for automotive vehicles came into effect in India from 1991. Since then, the exhaust mass emission certification tests are conducted on a prototype vehicle for emission compliance before commencing commercial production. The exhaust emission norms are reviewed and tightened after every five years. This should lead to a better emission control system in new vehicles. But the old vehicles which are designed prior to emission control era continue to emit heavily due to their inherent design and condition. The problem of in use vehicle emissions will be on the rise with the low scrappage rate of old vehicles in India. The impact of implementing tighter norms for new vehicles on ambient air quality can be felt only after a period of about 10 years. To have an effective improvement in ambient air quality levels, it is necessary to identify the gross polluters and retune them for bringing their emissions to an acceptable level.

In this work a simple 1-D model for the macro kinetic conversion behaviour of a commercial automotive Three-way-exhaust catalyst for a Turbocharged DI-Gasoline-Engine is realized using GT-Power. A detailed reaction kinetic model to predict the activity of the commercial three way catalyst has been adopted from Young-Deuk [1], considering all possible reactions in the catalytic converter based upon the Langmuir-Hinshelwood mechanism. 1D model was later modified for the laboratory scale catalyst and validated against synthetic gas test bench data.

Antiroll bar plays an important role in rollover stability of the vehicle. But not only does it limit the vehicle roll during cornering, but also alters the lateral load transfer between the tracks, which in turn affects the cornering performance of the vehicle. This paper deals with the design and mathematical modeling of antiroll bars to reduce the body roll of the vehicle from 1.5°/g to less than 1.0°/g. Rear bar uses a conventional torsion type bar but the front anti roll mechanism is an unconventional antiroll bar using a rotating double cantilever mechanism. Mathematical modeling is done for pushrod rod actuated antiroll mechanisms to simulate its non-linear roll rates. Antiroll bars for front and rear are designed for the calculated stiffness. Finite Element Analysis of antiroll bar and its components is done and the mechanism is tested on the vehicle. Steady state tire model parameters are generated by curve fitting tire testing data into pacejka coefficients.

The objective of this study is to develop, demonstrate and validate the methodology of external aerodynamic analysis of a State Road Transport bus for prediction of drag coefficient and its impact on fuel consumption with experimental validation. It has been verified that vehicle consumes around 40% of the available engine power to overcome the air drag. This gives us a huge scope to study the effect of aerodynamic drag. Baseline model of State Road Transport Bus was evaluated for estimating fuel consumption using Computational Fluid dynamics (CFD) methodology. The CFD results were validated with the experimental data with less than 10% deviation. Bus design was optimized with an objective of reducing the fuel consumption with parameters like angle of windshield, rounding and tapering corners and rear draft angle. Optimized bus design is also ensured to meet functional specifications as per AIS052.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

It is an established fact that virtual knowledge based engineering has revolutionized R & D activities by streamlining processes, ensuring productivity and accuracy. This has resulted in freeing up time for quality interpretational work and decision making for engineering the best of products. Subsequently, homologation is a mandatory requisite activity for product signoff. It certifies the quality of the product and is an important factor in giving the product an authenticity for sale in the market. Homologation entails compliance to regulations existing in form of well-established standards which elaborate systematic and detailed guidelines on conducting physical testing for automotive systems, sub-systems or components for specific vehicle types.

Suspension development is one of the key steps in a complete vehicle development program. Computer simulation and analysis tools such as Multi Body Dynamics (MBD) simulation are used to refine initial concept and suspension parameters. Later on when a physical prototype is available the suspension system can be experimentally optimized at vehicle level. In this paper a new methodology is proposed which integrates virtual and experimental tools so that design, development and validation of the suspension system is carried out in the early phase of the vehicle development cycle with actual suspension components and without the need of a vehicle prototype. With this new approach, the design of any critical suspension components such as dampers can be optimized at the vehicle level. The new approach consists of combining the actual physical components on loading rig in closed loop with vehicle dynamic model running in real time.