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Two-poster rig plays a very important role in accelerated durability evaluation in a motorcycle industry, similar to what a four-poster rig does in a car industry. The rig simulates the exact road conditions in the vertical direction through tire coupling by applying feedback control on displacement. On account of its ability to simulate to the exact customer usage conditions, it reproduces the failures realistically as it happens on the field. However, as complete vehicle is required for testing on the rig, the testing happens mostly in the advanced stages of product development. Any failures beyond the concept stage have a huge impact on the development time and cost and the same should be avoided. Therefore, in this paper, a virtual testing methodology is proposed, based on which potential failures on the vehicles can be captured at the concept design stage itself. An ADAMS model of a motorcycle was created.

In commercial vehicles, exhaust system is normally mounted on frame side members (FSM) using hanger brackets. These exhaust system hanger brackets are tested either as part of full vehicle durability testing or as a subsystem in a rig testing. During initial phases of product development cycle, the hanger brackets are validated for their durability in rig level testing using time domain signals acquired from mule vehicle. These signals are then used in uni-axial, bi-axial or tri-axial rig facilities based on their severity and the availability of test rigs. This paper depicts the simulation method employed to replicate the bi-directional rig testing through modal transient analysis. Finite Element Method (FEM) is applied for numerical analysis of exhaust system assembly using MSC/Nastran software with the inclusion of rubber isolator modeling, meshing guidelines etc. Finite Element Analysis (FEA) results are in good agreement with rig level test results.

In this study, 3D air-flow-field evolution in a single cylinder optical research engine was determined using tomographic particle imaging velocimetry (TPIV) at different engine speeds. Two directional projections of captured flow-field were pre-processed to reconstruct the 3D flow-field by using the MART (multiplicative algebraic reconstruction technique) algorithm. Ensemble average flow pattern was used to investigate the air-flow behavior inside the combustion chamber during the intake and compression strokes of an engine cycle. In-cylinder air-flow characteristics were significantly affected by the engine speed. Experimental results showed that high velocities generated during the first half of the intake stroke dissipated in later stages of the intake stroke. In-cylinder flow visualization indicated that large part of flow energy dissipated during the intake stroke and energy dissipation was the maximum near the end of the intake stroke.

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.

Plastics (polymers) are nowadays clearly a material of choice in all application sectors including in Automobile sector. Automotive manufacturer have relived on new technology for vehicular accessories which are all made-up of different polymers like Acrylonitrile-Butadiene-Styrene (ABS), Poly Carbonates, Poly Methyl Methacrylate (PMMA), Acrylic, glass, resin etc. Although these components offer an impressive range of attractive properties, the effect of climatic conditions on the durability and performance of these materials is not fully understood. The durability, performance and rate of deterioration of these products are all significantly influenced by both the material composition, as well as the climatic conditions to which they are exposed. The degradation/ variation of the mechanical properties of the specimen treated at different environmental/ atmospheric conditions are a primary concern when recommending such a composite for particular use.

In gasoline direct injection (GDI) engines, air-fuel mixture homogeneity plays a major role on engine performance, especially in combustion and emission characteristics. The performance of the engine largely depends on various engine operating parameters viz., start of injection, duration of injection and spark timing. In order to achieve faster results CFD is becoming a handy tool to optimize and understand the effect of these parameters. Therefore, this study aims on evaluating the two injection parameters viz., single and split injection to evaluate different flame characteristics. Novelty in this study is to define five different parameters which are called α, β, γ, δ and η the details of which are explained in the paper. In order to understand the flame characteristics, these five parameters are found to be very useful. In the present study, a single-cylinder, two-valve, four- stroke engine which is used in two-wheelers in India is considered for carrying out the CFD analysis.

Accurate quantification of residual stresses is critical to predict expected fatigue life of the component. Quantification of residual stresses by X ray diffraction method offers substantial accuracy in results as compared to other methods of stress measurements. Depending on component processing and geometry, various stress measurement techniques are used to analyze stress patterns induced by these processing. This paper describes some of the stress measurement techniques by results obtained on two compressor valve (reed) samples which are undergone different processing. First reed sample is analyzed after blanking operation which is expected to give low compressive or tensile stresses whereas second reed sample is analyzed after tumbling operation which is done to get high compressive stresses.

In the present study, a 17 kW, stationary, direct- injection diesel engine has been converted to operate it as a gas engine using producer-gas and compressed natural gas (CNG) as the fuels on two different operational modes called SIPGE (Spark Ignition Producer Gas Engine) and DCNGE (Dedicated Compressed Natural Gas Engine). The engine before conversion, was run on two other modes of operation, namely, diesel mode using only diesel and producer-gas-diesel-dual-fuel mode with diesel used for pilot ignition. The base data generated on diesel mode was used for performance comparison under other modes to ascertain the fuel flexibility. A technology development and optimisation followed by performance confirmation are the three features of this study. The exercise of conversion to SIPGE is a success since comparable power and efficiency could be developed. DCNGE operation also yielded comparable power with higher efficiency, which establishes the fuel flexibility of the converted machine.

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.

The effect of different cold- rolling and cryo-rolling routes on the strength and ductility of Al-6061 alloy was thoroughly investigated. Rolling decreased the grain size and increased the strength according to the Hall-Petch relationship. However subjecting the samples to ageing at different temperatures and for different time period increased the strength and improved the ductility. The ductility was improved due to the rearrangement and even decrease in dislocation density due to recovery and recrystallization during ageing while the strength was maintained due to ageing. Evolution of microstructure was investigated by optical microscopy, scanning electron microscopy. Preliminary hardness measurements coupled with tensile tests indicate the improvement of both yield strength and ductility. The disparity in ultimate tensile strength, yield strength and the elongation to failure with different ageing temperatures and for different time period is determined and discussed.

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.

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.

The study of aerodynamic forces in hypersonic environments is important to ensure the safety and proper functioning of aerospace vehicles. These forces vary with the angle of attack (AOA) and there exists an optimum angle of attack where the ratio of the lift to drag force is maximum. In this paper, computational analysis has been performed on a blunt cone model to study the aerodynamic characteristics when hypersonic flow is allowed to pass through the model. The flow has a Mach number of 8.44 and the angle of attack is varied from 0º to 20º. The commercial CFD solver ANSYS FLUENT is used for the computational analysis and the mesh is generated using the ICEM CFD module of ANSYS. Air is selected as the working fluid. The simulation is carried out for a time duration of 1.2 ms where it reaches a steady state and the lift and drag forces and coefficients are estimated. The pressure, temperature, and velocity contours at different angles of attack are also observed.

Minimum weight and high-efficiency gearboxes with the maximum service life are the prime necessity of today’s high-performance power transmission systems such as automotive and aerospace. Therefore, the problem to optimize the gearboxes is subjected to a considerable amount of interest. To accomplish these objectives, in this paper, two generalized objective functions for two stage spur-gearbox are formulated; first objective function aims to minimize the volume of gearbox material, while the second aims to maximize the power transmitted by the gearbox. For the optimization purpose, regular mechanical and critical tribological constraints (scuffing and wear) are considered. These objective functions are optimized to obtain a Pareto front for the two-stage gearbox using a specially formulated discrete version of non-dominated sorting genetic algorithm (NSGA-II) code written MATLAB. Two cases are considered, in the first with the regular mechanical constraints.

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.

Light weighting is significant in for automotive industry as it helps in less fuel consumption and to achieve better performance. Aluminium is a candidate material for light weighting. To design a component made of aluminium material, it is necessary to understand the fatigue performance of the material. In this paper, a study is carried out to understand the fatigue performance of aluminium 6xxx series alloys at an early stage of design without carrying out comprehensive fatigue testing. Coffin Manson Parameters are used to predict fatigue life. This research focusses on determining the gaps in existing models for aluminium alloys by carrying out comprehensive review of various models developed for 6xxx series which uses monotonic tensile data. Two models are developed and the predicted fatigue properties for this class of material are further compared with experimental fatigue, monotonic data and literature.

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.