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Engine experiments have revealed the importance of fuel condensation on the emission characteristics of low temperature combustion. However, direct in-cylinder experimental evidence has not been reported in the literature. In this paper, the in-cylinder condensation processes observed in optically accessible engine experiments are first illustrated. The observed condensation processes are then simulated using state-of-the-art multidimensional engine CFD simulations with a phase transition model that incorporates a well-validated phase equilibrium numerical solver, in which a thermodynamically consistent phase equilibrium analysis is applied to determine when mixtures become unstable and a new phase is formed. The model utilizes fundamental thermodynamics principles to judge the occurrence of phase separation or combination by minimizing the system Gibbs free energy.

The Extended Coherent Flamelet Model (ECFM) is limited to lower order upwinding schemes to minimize the numerical discrepancy between species and tracers, which can lead to inaccurate estimates of the progress variable and consequently negative conditional mass fractions in the burned gases after ignition. The recently developed Species-Based ECFM (SB-ECFM) removes the species tracers from the definition of the progress variable, and allows the use of higher order schemes. In this study, SB-ECFM is coupled with the Imposed Stretch Spark Ignition Model (ISSIM) to simulate a spark-ignition engine, the transparent combustion chamber (TCC) engine. To examine the spatial discretization effect and demonstrate the improvement due to using higher order schemes, Reynolds-Averaged-Navier-Stokes (RANS) simulations performed with a first-order upwinding scheme and a second-order central differencing scheme are compared.

Surface film formation is an important phenomenon during spray impingement in a combustion chamber. The film that forms on the chamber walls and piston bowl produces soot post-combustion. While some droplets stick to the wall surface, others splash and interact with the gas present inside the combustion chamber. Accurate prediction of both the film thickness and splashed mass is crucial for surface film model development since it leads to a precise estimation of the amount of soot and other exhaust gases formed. This information could guide future studies aimed at a comprehensive understanding of the combustion process and might enable development of engines with reduced emissions. Dynamic structure Large Eddy Simulation (LES) turbulence model implemented for in-cylinder sprays [1] has shown to predict the flow structure of a spray more accurately than the Reynolds-averaged Navier-Stokes turbulence model.

The increase in computational power in recent times has led to multidimensional computational fluid dynamics (CFD) modeling tools being used extensively for optimizing the diesel engine piston design. However, it is still common practice in engine CFD modeling to use constant uniform boundary temperatures. This is either due to the difficulty in experimentally measuring the component temperatures or the lack of measurements when simulation is being used predictively. This assumption introduces uncertainty in heat flux predictions. Conjugate heat transfer (CHT) modeling is an approach used to predict the component temperatures by simultaneously modeling the heat transfer in the fluid and the solid phase. However, CHT simulations are computationally expensive as they require more than one engine cycle to be simulated to converge to a steady cycle-averaged component temperature.

A three-dimensional model of a diesel engine intake port was established and was verified by steady-flow test. Based on this model, the influence of intake valve lift on the flow capacity of intake port was studied and a design method of maximum valve lift was put forward. The results show that, under different intake pressure and relative pressure difference conditions, the discharge coefficient increases first and then converges with the increase of valve lift. Under the same valve lift condition, with the increase of relative pressure difference, the discharge coefficient decreases slightly in subsonic state and decreases sharply from subsonic state to supersonic state, but the mass flow rate increases slightly. The optimum ratio of valve lift and valve seat diameter is related to relative pressure difference, it increases first and then keeps constant with the increase of relative pressure difference.

Prognosis is used to improve system availability. This is achieved by minimizing system downtime with the help of mechanisms that senses the degradation in the system health to predict the ‘time-to-failure’ of the system. Degradation in the system’s health is measured by sensing the early signs of aging and wear and tear of the system components. This requires knowledge of all the failure modes of the system along with patterns of behavioral changes in the individual components of the system while it continues to age. Prognosis methods and mechanisms are still evolving. So, no comprehensive guidelines or framework standards exist as of today that can provide reliable and standardized prognosis solutions to the end user customers. The intent of devising such a framework and guidelines is to improve and standardize the implementation of prognosis solutions so that; it will be more effective to all stakeholders from the perspective of safety, cost and convenience.

With increasing road traffic and pollution, it becomes responsibility for all OEM to increase fuel efficiency and reduce carbon footprint. Most effective way to do so is to reduce weight of the vehicle and more use of ecofriendly recyclable material. With this objective we have come up with Light weight, cost effective sustainable design solution for Injection moulded RQT (Rear quarter trim). It is an interior plastic component mounted in the III row of the vehicle. This is required to ensure inside enhanced aesthetic look of the vehicle and comfort for 3rd row passengers. Conventionally RQT of vehicle with 3rd row seating is made using plastic material (PP TD 20). With the use of plastic moulded RQT there is a significant weight addition of around 6 kg per vehicle along with reduced cabin space, huge investment and development time impact.

Tyre exterior noise legislation (pass-by) is becoming more stringent with time. To cater to these requirements, it is very important to understand the tyre noise generation and enhancing mechanisms such as air pumping, air turbulence, pipe resonance, horn effect in high frequency region from 500Hz to 4000Hz. These phenomena are affected by air flow around and within the tyre pattern hence, CFD based approach is chosen for tyre exterior noise. The CFD based methodology helps in fine tuning the tread pattern to reduce aero acoustic noise level which leads to reduction in the product design cycle time. In present study, 3d transient CFD aero-acoustic modelling approach results were validated against the anechoic tyre rolling noise test data which captures the air-born noise mechanisms for frequency range of 1 kHz to 4 kHz.

Modern cars now come with sophisticated telemetry which often involve connecting to the internet over mobile telephone networks or Wi-Fi. The telemetry or cloud functions of the car is typically handled by a Telematics Control Unit or the Infotainment System. The microcontrollers (Host Processor) powering the ECUs are very powerful and often have operating systems such as Linux or QNX to drive the large displays or perform modem functionalities. These powerful microcontrollers take several seconds to startup and does not offer hard real-time performance - both of which are critical to handle the vehicle CAN network. Hence, it is common to include a less powerful microcontroller to the ECU to perform the management of the vehicle CAN network. These smaller microcontrollers (Vehicle Processor) can startup fast and provide hard real-time performance.

Handling performance of a vehicle is a key characteristic determining the response of vehicle under different operating scenarios. An insight into these vehicle-handling characteristics at early stage can be extremely useful in the design and development process. Tire characterization and tuning is important and mandatory to scrutinize each functional and individual parameter of tire. Tire force and moment data is having a significant effect in vehicle handling. Segregation of tire parameter, which is contributing vehicle-handling performance, helps to identify and perform optimization for improvisation. The main objective of this study is development and integration optimized 1D tire model into multibody dynamics model of the vehicle to observe various vehicle compliances towards its handling performance target.

The concept definition phase of typical vehicle development focuses on the architecture definition and optimization based on different constraints/requirements. With the focus on Sustainability, the architecture optimization process must include “Light-weighting” as an optimization criterion. With only concept vehicle architecture available, the vehicle weight estimation becomes judgmental & inaccurate. This paper aims to address this deficiency with a new analytical approach for vehicle weight estimation. The new approach for vehicle weight estimation is a “bottom-up” approach using parametric models for each system weight with the inputs being the relevant vehicle specifications driving the system engineering. For size/shape-driven (rather than functional) systems, the models are content-based & segment-based. The parametric models are then iterated for multiple architecture concepts & specifications and the optimum concept (meeting all functional & business constraints) is chosen.

Nowadays more and more people are concerned about the safety rating of their vehicle. The safety rating depends on the ability of the car to minimize the injury to the occupants post-crash. Crashworthiness of the vehicle is determined by carrying out various tests such as static and dynamic tests. Side crashes are one of the leading causes of fatal injury following front crashes. Side door strength is dependent on the door components such as latch and striker, hinge, door beam etc. Lateral stiffness is contributed significantly by the side door beam in the door structure. The side door beam limits the side intrusion into passenger compartment. This paper emphasizes the effect of intrusion beam materials and orientation in the side door strength with a numerical approach using ANSYS tool. These factors affect the strength and weight of the door. The simulation study with respect to door design is cost-effective and time-saving.

During flight an emergent circulatory flow pattern named vortex is observed at wing tips producing induced drag. An approach to reduce this effect is by implementing winglets. Winglets are small wing-like lifting surfaces, fitted at the tip of some wings, usually with the objective of decreasing trailing vortex drag and thereby increasing the aerodynamic efficiency of the wing. The aim of the project is to design and analyze the effect of winglets for Cessna 152 by varying the cant angle and sweep angle. This model has been selected since it provides a good choice for Pilots first airplane. A baseline wing model was designed in CATIA V5, correspondingly wings with winglet models were designed with a fixed taper ratio of 0.2 and different cant and sweep angles. The lift to drag ratio is evaluated at different angles of attack by varying winglet design parameters.

The present numerical analysis aims at studying the effect of changes in profile of van on aero-acoustic noise and aerodynamic drag. The numerical analysis is carried out using commercial CFD software, ANSYS Fluent, with k-epsilon & Large Eddy Simulation turbulence models. In present study five models of truck are analysed, including baseline model at different Reynolds numbers, namely 0.391, 0.415 and 0.457 million. In order to reduce the aero-acoustic noise, various profile modifications have been adapted on existing van model by adding a top and bottom diffuser at the rear of the truck. The comparison has been done with respect to coefficient of drag, coefficient of pressure, pressure contours for all four cases.

Engine in-cylinder flow structure governs the combustion process and directly influences emission formation and fuel consumption at the source. In naturally aspirated DI diesel engine, combustion process coupled with low pressure mechanical fuel injection systems set different requirements for inlet port performance. In-cylinder swirl needs to be optimized for efficient combustion to meet emission levels and fuel consumption targets. Thus, intake port design optimization process becomes a vital requirement. In the present paper intake port design optimization is carried out for single cylinder naturally aspirated engine using mechanical fuel injection systems. The objective is to investigate in-cylinder flow field developed by intake port designs, study the effects of geometrical details of various port cross sections on flow velocity and pressure fields and establish a relationship with intake port performance parameters i.e. swirl and flow coefficient.

By looking current scenario, engine development lead time was reducing day by day to enter early in the competitive market and to compete as early as possible. During initial engine development phase, it was very important to know how engine operating temperatures were affecting to piston pack and related system. Conventionally temp plug method was used to capture the piston temperature, but it was time consuming, much costly, for every test condition, new temp plug pistons required, if unfortunately, any hot shutdown happened during the test, again full test needs to be restarted with new set of temp plug pistons and many more limitations. So, for Cummins engine we used Telemetry technique to measure the piston temperature ONLINE and in real time. Piston telemetry enables the telemetric transfer of piston data from internal reciprocating and rotating components. The pistons had wireless telemetry to send real time steady state and transient data from within engines.

This paper presents the natural and artificial weathering behavior of different soft skin materials such as leather, leatherette and textiles used for automotive seat cover applications. The objective of this study was to understand the physical and aesthetical changes occurring at these flexible materials under sun UV light and heat exposure. The natural weathering study under glass exposure was carried out as per ASTM G 24 at natural weathering site location and artificial weathering as per SAE J2412 at lab. The material was observed for surface changes such as color, texture, crack and physical changes like flexibility and hardness during the exposure. The sample exposed at natural weathering data for every 15 days were recorded, and artificial weathering for every 100 hours were recorded.

The favorable mechanical properties of Composite materials are excellent stiffness/weight and strength/weight ratios, easy formability and corrosion resistance. The application of composites in structural components is still limited by the difficulty in predicting their service lives. The objective of this research paper is to develop and evaluate damage initiation or delamination onset and growth in a C-C composite 8 layered pre-preg material 3D laminate model (dimension 25x3.4x85mm and ply thickness 1mm) under loading conditions without crack using ANSYS Autodyne tool subjected to a uni-axial load of 40N at the free end. Mapped quadrilaterals mesh is generated with 2610 nodes and 1792 elements. Cohesive Zone Model (CZM) formulations are more powerful than Fracture Mechanics approaches because they allow the prediction of both initiation and crack propagation.

Single point Incremental forming (SPIF) is a metal forming process that has achieved impeccable quality since the early 1990s. ISF is a very limited twisting process in which an improved device that must be used after a particular direction travels on a metal sheet to form the desired shape. Process parameters such as axial feed (mm), feed (mm / min), tool diameter (mm) and depth (mm) at the interface between samples during SPIF greatly affect the quality of the cone. Maximum thinning (mm), cone height (mm), wall angle (mm), formation time (minutes), etc. The purpose of this study was to study these parameters by improving the cone mass formed by VMC. For a detailed study of these parameters, experiments were performed using the orthogonal array L9. Output parameters such as mechanical quality effects were analysed using COPRAS (Complex Proportional Assessment of alternatives) and ANOVA.

Road accidents are increasing now-a-days, Safety of pedestrian is the great concern. In average, 10% of urban pedestrian accidents are fatal. Statistics show that the impact on front side of cars is the major cause of pedestrian deaths (83.5%). The function of a vehicle’s engine hood is to keep its engine covered and allow access to the engine compartment as required for maintenance and repair. The hood structure not only protects the engine cavity, but also keeps pedestrians away from the parts of that cavity. The absorption capability and stiffness of hood structures are the key points considered when designing a vehicle’s hood. The impact of the pedestrian head on automotive hood results in major injuries and sometimes in death. Conventional engine hood results in greater Head Injury Criterion (HIC) values. GFRP pyramidal lattice core structures are used in automobiles which is used for good energy absorption.