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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.

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.

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.

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.

BS-VI or equivalent development calls for tremendous efforts in concept investigation and calibration for engine out, after treatment, diagnostic checks, off-cycle emissions, field performance, component safety etc. Achieving calibration quality for all these tasks is very challenging considering development time and cost with conventional physical testing approach. Present article focuses on assessment of testing and calibration using virtual approach. To prove and validate this approach, a six-cylinder heavy duty diesel engine is selected and configured in HiL environment. The engine plant model is built offline and validated with base engine data at steady state and transient operations and RT model is integrated with ECU hardware. Data for plant model corrections is generated with short measurement campaign. Refined real time plant model is prepared for evaluating different calibration strategies on virtual test bed environment.

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.

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.

In internal combustion engines, rate of fuel burning known as burn rate is a simplified representation of complex in-cylinder combustion process. It is considered as a prime input especially in 1D simulation tool for all important thermodynamic studies. A novel parametric model for prediction of burn rate in heavy duty Direct Injection (DI) diesel engine has been introduced in the present work. A wide range of experimental data with more focus on higher load points with different in-cylinder combustion characteristics is considered and burn rates have been generated using measured pressure trace. Generated burn rates have been studied over different phases of combustion. These burn rate shapes have been analyzed to understand the effect of fuel injection system, air management subsystem parameters along with in-cylinder conditions on combustion. Different mathematical modelling approaches for burn rate approximation like Wiebe function have been studied.

Autonomous driving is looked upon as solution for future of automotive vehicles. The technology has tremendous possibilities to improve safety, fuel economy, comfort, cost of ownership etc. The project to develop an autonomous controller from scratch was undertaken, with objective to drive under selected test scenarios. The car, modified to drive using this autonomous controller, is able to handle these scenarios. The key scenarios include ability to successfully drive on tracks with well-marked lanes, Follow the route as per selected trip plan file, recognize and follow all traffic road signs, traffic signals en-route, identify other vehicles on the road or pedestrians in the lane and take the appropriate action. The development was carried out using frugal engineering approach. As the Autonomous Vehicle technology is still under development, the standard proven published approaches are not available.

Diesel engine generators are commonly used as a power source for various industrial and residential applications. While designing diesel generator (DG) enclosures requirements of noise control, ventilation and physical protection needs to be addressed. Indian legislation requirement demands DG enclosure insertion loss (IL) to be minimum 25 dB. However for certain critical applications like hospitals, residential apartments customer demands quiet DG sets than the statutory limits. IL targets for such application ranges between 35-40 dB. The objective of this paper is to develop methodology to design ‘Super Silent’ enclosure with IL of 35 dB by Statistical Energy Analysis (SEA) approach for small capacity DG set. Major challenge was to achieve IL of 35 dB with single enclosure and making use of SEA technique for small size enclosure wherein modal densities is very less. Major airborne noise sources like engine, radiator fan and exhaust were modelled by capturing noise source test data.

Recent trends towards design of High Performance Diesel engines creating more challenges in the area of design, durability and NVH aspects of components and systems. In particular, Valvetrain system of High Speed application engines is one of the most critical and complicated dynamic system in terms of precise control of events, max. Lift, control over accelerations and vibration related issues. This can be tackled by designing the cam profile for better valve train dynamics. High frequency components and/or excessive jerks in a cam profile are important sources of cam-follower vibrations. There are various techniques of designing cam profile to achieve controlled valve train dynamic behavior at high speed operations. Present paper discuss the impact of various cam profile options designed using Polydyne, N-Harmonic and B-Spline methodologies on a field problem of cam wear for high speed engine application.

To meet the latest trends in Internal Combustion engines regarding efficiency, emissions and durability, an integrated approach to engine development is required. This paper describes about a Robust, Reliable and an integrated approach used in design and development of an engine for high power density which can be adopted for both Off-highway application as well as Genset application. The engine is developed to meet US - EPA Tier-III Emission Norms and MoEF (Genset Emission Norms for India formulated by Ministry of Environment and Forest) emission norms respectively. This paper discusses various technologies applied in developing this engine to achieve high power density, low exhaust emissions, and low noise and vibrations. This 4 valve per cylinder engine is created largely within a digital environment using the latest computer aided design (CAD) and computer aided engineering (CAE) techniques and simulation tools.

The Partially Pre-mixed Charge Compression Ignition (PCCI) combustion was experimentally and computationally investigated with retarded injection timing for mixture homogeneity and for lower emissions. PCCI combustion concept was experimentally evaluated with retarded injection timing close to TDC with high EGR levels up to 50%. The CFD analysis has carried out for mixture homogeneity with different injection pressures and timings. A 4-cylinder TCIC engine having 2valves/cylinder were selected for experiments and speed vs. torque mapped for LCV applications. A Visio technique has been used to study the in-cylinder combustion. After fine tuning of injection pressure, injection timing and EGR ratio over entire range of engine speeds and loads, a 13-mode ESC test cycle has been carried out for EURO-IV and EURO-V emissions. Experimental results shows that it is possible to meet EURO-IV emissions with combined PCCI-DI combustion concept with economical aftertreatment solution.

The Indian automotive industry has taken a big leap towards stringent Bharat Stage VI (BS VI) emission standards by year 2020. A digital driven design and development focusing on innovative and commercially viable technologies for combustion and exhaust after-treatment system is the need of the time. One-dimensional (1D) simulation serves as a best alternative to its counterparts in terms of obtaining faster and accurate results, which makes it an ideal tool for carrying out optimization studies at system level. In this work, 1D chemical kinetics modelling and analysis of exhaust after-treatment system (EAT) for a heavy-duty diesel has been performed using GT-Power. Initially, a single site 1D model for a diesel oxidation catalyst (DOC) has been developed and then, a two-site, 1D model for a selective catalytic reduction (SCR) catalyst was also developed based on reactor data.