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The paper describe investigations on the vibration characteristics of a gasoline engine due to piston slap and a diesel engine due to combustion. Engine parameters and vibration data were recorded and time series signals were obtained. The effect of speed, load and other engine parameters on vibration is investigated. Vibration due to piston slap is analysed with reference to major-minor thrust relationship, cylinder to cylinder variation, piston-slap force diagram and vibration-frequency curves. The experimental results suggest that all reciprocating engines would exhibit a complex vibration pattern due to piston slap at harmonic series of discrete frequencies, and the reason for this is analysed. The vibration transmitted by engine structure in response to the in-cylinder pressure development is termed here as ‘Vibration due to Combustion’ and is assessed from the spectrum of the Combustion Pressure curves and their derivatives in terms of time.

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.

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.

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 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.

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.

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.

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.

In this work, the effect of tool rake angle and cutting speed on residual stresses of tool was studied, the rake angles of 0°, 5°, 10°, 15°, and 20° and a constant clearance (Relief angle) of 8° were used to turn bright mild steel on the lathe machine, A total of 15 experiments were carried out with three different cutting speeds (37.69, 59.37, 94.24 m/min) for each rake angle, keeping the feed rate and depth of cut constant. During the experimentation, the residual stresses were measured using an x-ray diffractiometer. This is all in order to explore the energy savings opportunities during regrinding of tools, useful production time and energy is being wasted due to regrinding or re-sharpening of tools when cutting tools got worn or blunt, selection of the rake angle which generate the optimum residual stresses in the tool, goes a long way in saving these time and energy.

Any metal component undergoes various treatments to get desired shape and desired properties. Some of the important properties are strength, hardness, % elongation etc. which comes under mechanical properties. These properties can be easily achieved through heat-treatment process. Typical example of heat-treatment processes are hardening and tempering in case of steel and aging process in case of aluminium alloys. Some of the new emerging materials viz. micro alloy steel does not require any hardening and tempering if cooling rate is maintained. Heat-treatment cycle depends on material grade and its alloying elements. A heat-treatment cycle for any grade is generally fixed based on conventional methods but they are not optimized. The need of hour is to optimize the heat-treatment cycle to improve productivity and energy consumption. Dilatometer is used to optimize heat-treatment cycle on sample level whereas simulation tools can be used for component level.

Gear whine can be reduced through a combination of gear parameter selection and manufacturing process design directed at reducing the effective transmission error. The process of gear selection and profile modification design is greatly facilitated through the use of simulation tools to evaluate the details of the tooth contact analysis through the roll angle, including the effect of gear tooth, gear blank and shaft deflections under load. The simulation of transmission error for a range of gear designs under consideration was shown to provide a 3-5 dB range in transmission error. Use of these tools enables the designer to achieve these lower noise limits. An equally important concern is the dynamic mesh stiffness and transmissibility of force from the mesh to the bearings. Design parameters which affect these issues will determine the sensitivity of a transmission to a given level of transmission error.

The present study discusses the effects of engine combustion, performance and emission features of methanol-gasoline blend fired lean burn Spark Ignition (SI) engine. Performance features such as Brake Power (BP), Brake Specific Fuel Consumption (BSFC), Brake Thermal Efficiency (BTE), tail pipe emissions namely Hydrocarbon (HC), Carbon Monoxide (CO), Nitrogen Oxide (NO), Carbon di Oxide (CO2) and combustion characteristics viz. in-cylinder pressure, Heat Release Rate (HRR), Cumulative Heat Release (CHR) and variation of mean effective pressure were measured and compared with that of neat gasoline. Experiments were conducted on a modified sole cylinder four-stroke compression engine (Kirloskar TAF1) to operate as SI engine with a compression ratio of 10.5:1. A new manifold injection system and ignition system were developed by replacing the fuel injection pump and injector.

A Generator set is comprised of mainly an Engine, Alternator and Chassis. High Horse-Power Generator development is challenging, with lots of complexities in physical and virtual validations. Creating high fidelity analytical model is always beneficial and economical at the design stages as it avoids repetitive tests on various design concepts. This paper reports analytical methods of developing an FEA model of a Generator for locomotive application and its correlation with Test. Highlighted as well are some of the challenges faced in FE modeling of a large Generator model (60 liters engine capacity) with node count of around 4 million. In this technique, Modal Analysis is first performed to capture the dynamic behavior. More than 95 % correlation is achieved between the FEA and test natural frequencies (Bending modes). Harmonic Analysis with Modal Superposition is then applied to understand the dynamic response of a Chassis under the action of engine vibratory loads.

The value of crash simulation has long been recognized by carmakers as an essential tool for vehicle development and certification programs. Driven by the need to minimize time-to-market for new models, cost reduction, and by consumer demand for safer cars and trucks, the industry is moving to newer technologies in crash simulation. Crash simulation provides an inexpensive means to quickly simulate the effects of a barrier crash by reproducing its basic elements - acceleration, velocity and displacement - in a nondestructive test. Crash event timing and accuracy of reproduction are critical performance factors. This paper describes the unique features and capabilities offered by a new generation of crash simulators.

In a developing country like India, Two-wheelers dominate the automotive market with around 80% market shares. In Indian city traffic conditions, driving a two wheeler is a tiresome job. Manual transmission makes this task even further uncomfortable. So an automatic transmission is a better solution. A new automatic transmission system is developed which can reduce fatigue of drivers. Steps of ARIZ (Algorithm for Inventive Problem Solving) were followed. Ideas or concepts for the design were proposed from various fields and were compared for various parameters like size, weight, complexity, manufacturability, feasibility, efficiency and cost. They were also compared with the existing transmission systems. Based upon the results of the comparison, 5 designs were selected and they were analyzed thoroughly. Finally one design was selected.