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The distribution of spray droplet sizes plays a pivotal role in internal combustion engines, directly affecting fuel-air mixing, evaporation, and combustion. To gain a precise understanding of droplet size distribution in a two-dimensional space, non-intrusive optical diagnostics emerge as a highly effective method. In the current investigation, two-dimensional (2D) diesel spray droplet sizes mapping using a simultaneous combination of planar laser-induced fluorescence (PLIF) and Mie-scattering techniques is introduced. The assessment of droplet diameter relies on the interplay between fluorescent and scattered light intensities which correspond the light based on volumetric droplets and surface area of the droplets. This calculation is made possible through the LIF/Mie technique. However, traditional LIF/Mie methods are plagued by inaccuracies arising from multiple light scattering.

A 2D finite element program, known as FAST_FORM2D, was developed at FTI to carry out section analysis in die design. Incremental method is employed and plane strain condition is assumed for 2D sections. Contact behavior and friction force are simulated by a developed algorithm. Therefore, the divergence problems related to the conventional contact techniques can be reduced or avoided. An adaptive mesh generation scheme is implemented to achieve computation efficiency. With the code, it is possible to evaluate tension, strain, thickness distributions and punch force at different stages for any 2D section cut from 3D panels. User can easily input or modify forming conditions to get the best solution.

Different Airbus Helicopters main rotor blade profiles were tested in different icing wind tunnels and for different icing conditions. One of the objectives of the accretion tests was to validate the use of 2D icing scaling laws established for fixed wing aircraft on helicopter blade profiles. Therefore, ice shapes resulting from tests with the same icing similarity parameters are compared to each other allowing the assessment of icing scaling laws for helicopter applications. This paper presents the icing scaling laws used at Airbus Helicopters on blade profiles, the different test set ups and test models and it presents the comparison of the ice shapes collected during the icing wind tunnel test campaigns.

The optimization of the vaporization and mixture formation process is of great importance for the development of modern gasoline direct injection (GDI) engines, because it influences the subsequent processes of the ignition, combustion and pollutant formation significantly. In consequence, the subject of this work was the development of a measurement technique based on the laser induced exciplex fluorescence (LIF), which allows the two dimensional visualization and quantification of the in-cylinder air/fuel ratio. A tracer concept consisting of benzene and triethylamine dissolved in a non-fluorescent base fuel has been used. The calibration of the equivalence ratio proportional LIF-signal was performed directly inside the engine, at a well known mixture composition, immediately before the direct injection measurements were started.

A helicopter blade profile was tested in the DGA Aero-engine Testing's icing altitude test facility S1 in Saclay, France during the winter of 2013/2014. The airfoil was a helicopter main rotor OA312 blade profile made out of composite material and with a metallic erosion shield. Dry air and ice accretion tests have been performed in order to assess the iced airfoil's aerodynamic behaviour. Several icing conditions were tested up through Mach numbers around 0.6. This paper presents the test setup, the test model and some of the test results. The test results presented in this paper include the ice shapes generated as well as dry air and iced airfoil lift and drag curves (polars) which were obtained with the real ice shapes on the airfoil.

The spatial distribution of internal exhaust gas recirculation (EGR) is evaluated in an optically accessible direct injection spark ignition engine using near infrared laser absorption to visualize the distribution of the H2O molecule. The obtained overall internal exhaust gas recirculation compares well to gas-exchange cycle calculations and the spatial distributions are consistent with those measured with inverse LIF. The experimental procedures described in this report are designed to be simple and rapidly implemented without the need to resort to unusual optical components. The necessary spectral data of the selected absorption line is obtained from the HITEMP database and is validated with prior experiments carried out in a reference cell. Laser speckle in the images is effectively reduced using a ballistic diffuser.

Growing interest in pollutant emission reduction has increased the importance of numerical simulations of spark ignition as a first step in IC engine combustion. In this work, we present simulations involving the coupling of flow, chemical reactions and molecular transport with the discharge processes. The main focus hereby is to investigate the early stages of the formation of a flame kernel in a two-dimensional, cylindrical geometry with electrodes. The computational results shown here include the initial shock-determined phase after the breakdown of the channel, but also the transition to flame propagation for a methane-air mixture.

Durability tests have been initiated on olefinic and production painted fascias. Both 2D and 3D tests have provided insights into Friction Induced Damage (FID) failure mechanics. Full scale, 3D tests of automotive fascia mimic the parking lot rubbing contact between cars with friction forces exceeding 5000. N. 2D tests provide the cost effective approach to materials research by isolating the failure mechanics in the upper 250 μm of the decorated TPO where the cosmetic damage is initiated. Initial findings show some olefinic paint, TPO combinations to be more damage resistant for realistic frictional contact scenarios.

2k clearcoat is the progressive step that is keeping coatings for elastomeric fascia in pace with the current automobile design, performance, and durability demands. Initially, rigid 2k coatings were applied over plastic for low temperature cure. Over metal, 2k rigid clearcoat produced a dramatic improvement in appearance and durability. Flexibility is the key attribute that a 2k clearcoat engineered for use over fascias must posses. Utilizing the same basecoat and primer, 2k flexible clearcoats are being successfully applied to flexible fascia, generating excellent appearance and outstanding durability.

Challenges surrounding OEM′s go far beyond to manufacture and delivery high quality vehicles. A perfect design and performance in the lowest cost possible is extremely essential to delivery to the customer the best vehicles. In order to guarantee all these targets, a robust process must be set to developed and implemented. It is known all process limitations, which faces the emergent markets and the lack of infrastructure considering the developed countries. All this limitations can deeply affect the robustness of the process. Some innovative solutions are becoming common from the engineering development combined with the manufacturing team to work out these limitations and provide excellent process stability. In this present paper it will be discussed the Bi component structural adhesive (2K PU epoxy) utilization to establish the process in the assembly line, mainly in order to improve parts dimensionally.

A historical review of the patents and literature pertaining to 3-valve stratified charge engines is presented in this paper. This very old invention appears to be a practical approach for the “clean engine” being sought for vehicular use since it has the intrinsic capability of simultaneously giving good fuel economy and producing minimal objectionable exhaust emissions. The prime requisites of this engine are a rich prechamber charge and a very lean main chamber charge regardless of prechamber volume, nozzle diameter, valving and spark plug location. Fuel-air equivalence ratios of the charges in the two combustion chambers are significantly important in order to achieve the proper optimization. These ratios should be about 15% rich for the prechamber and 15 to 30% lean for the main chamber at the moment of ignition.

Fine packaging is important for the bicycle transmission design. We are proposing a split power continuously variable transmission (SPCVT) operated with one mode. The planetary gear unit (PGU) in the SPCVT consists of two epicyclic gear trains. Both epicyclic gear trains do not include any ring gears to minimize the overall diameter of the transmission. A variator is connected to the PGU as a type of variable bridge. The variator involves two rotor pairs contacting on concave-convex spherical surfaces. This new mechanism of the variator shows a strong possibility to get high power density in comparison with other existing traction drives. A four-bar linkage is used to locate the counter rotor assembly exactly in the contact points of the rotor pair and extend the range of variator speed ratio. The crank is pulled by the wire connected to the speed control lever on the handle of bicycle.

Due to the requirements of the market, engine manufacturers and their suppliers must develop new products in a short lead time, with high quality, high reliability and lowest possible costs. A method to obtain a short lead time for a complicated aluminum cylinder head is the design in 3 D CAD and the use of simultaneous engineering. A practical example shows the design of a 16-valve cylinder head in 3 D CAD (Catia). The cylinder head supplier received a CAD-tape with the main dimensions such as valve locations, shape of the combustion chamber and ports and location of the bolts. A design team completed the cylinder head design in 3 D CAD in consideration of the needs for foundry technology, casting tool design and machining of the part. Special casting tools for the prototyping were manufactured parallel to the cylinder head design.

The term “3 inch ice shapes” has assumed numerous definitions throughout the years. At times it has been used to generally characterize large glaze ice accretions on the major aerodynamic surfaces (wing, horizontal stabilizer, vertical stabilizer) for evaluating aerodynamic performance and handling qualities after a prolonged icing encounter. It has also been used as a more direct criterion while determining or enforcing sectional ice shape characteristics such as the maximum pinnacle height. It is the authors’ observation that over the years, the interpretation and application of this term has evolved and is now broadly misunderstood. Compounding the situation is, at present, a seemingly contradictory set of guidance among (and even within) the various international regulatory agencies resulting in an ambiguous set of expectations for design and certification specialists.

This paper will describe the development of the 3-load cell tumble meter. This is a new method for measuring the tumble component of in-cylinder mixture motion. In-cylinder mixture motion is an important parameter for understanding and improving combustion stability of piston engines.

Engineers need to have a basic understanding of intellectual property: patents, trademarks, copyrights and trade secrets. This article is designed to serve as an introduction to patents as well as a guide for the technical professional who may or may not have the assistance of corporate legal counsel. Practical approaches to the three common issues that engineers are likely to get involved in: patent searching a product; avoiding patent infringement and protecting a new product idea are covered. Many facts about patents and intellectual property are introduced and a few myths are exposed.

The upcoming latest 3-wet Technology is the most ideal design for a Green field project as well as for a brown field facility which provides the best of both worlds. The foremost take away for a brown field project emanates from this technology which demands a smaller foot prints & hence could accommodates a capacity higher than what was perceived during the green field project planning thus saving millions of dollar of investment & giving that extra capacity which today the BRIC countries are thriving for. Apart from making the ideal investment choice, 3 Wet Technology provides impetus to business case in terms of reduction of VOC emission, Energy consumption, Material and labor cost and gaining on Green Environment front as well as leading to smart and Efficient-Paint-Process. The paper depicts the journey of roll out of 3-Wet process in Ford India and creating the bench mark in terms of product quality and process standards and manufacturing practices.

The objective of this paper is to compare the external anthropometry of 3 and 6 year old French children with the corresponding existing crash test dummies. An anthropometry study has been performed on about 70 (respectively 80) French children aged 3 years (respectively 6). More than 40 external measurements have been acquired on each subject. They include dimensions in standing and sitting positions: heights, lengths, circumferences, weight, etc. Mean, standard deviation, minimum and maximal values are given and compared with other existing international databases. From a global point of view, dimensions observed in this study appear 12% higher than in others. Dimensions are more specifically compared with corresponding crash test dummies in order to evaluate the validity of these anthropomorphic test devices.

Today turbo-diesel powertrains offering low fuel consumption and good low-end torque comprise a significant fraction of the light-duty vehicle market in Europe. Global CO₂ regulation and customer fuel prices are expected to continue providing pressure for powertrain fuel efficiency. However, regulated emissions for NO and particulate matter have the potential to further expand the incremental cost of diesel powertrain applications. Vehicle segments with the most cost sensitivity like compacts under 1400 kg weight look for alternatives to meet the CO₂ challenge but maintain an attractive customer offering. In this paper the concepts of downsizing and downspeeding gasoline engines are explored while meeting performance needs through increased BMEP to maintain good driveability and vehicle launch dynamics. A critical enabler for the solution is adoption of gasoline direct injection (GDi) fuel systems.

A 3-D analysis of the flow through a multihole, V.C.O. (Valve Covered Orifice) nozzle for D.I. Diesel Engine has been carried out. The analysis was performed by means of a finite element code. The nozzle comprises five injection holes. Aims of the analysis were: the investigation of the pressure drops along the conical clearance between the needle and the nozzle; the evaluation of the energy losses in the injection holes; the disclosure of the velocity profile at the injection hole outlets. the differences of flowrate for each hole with geometrical asymmetries. This kind of analisys is the first step of a more complete spray analysis; in fact, the spray from an injection hole is influenced by the injection pressure and the velocity profile. In particular, the needle lift and the needle tip deviation have been parametrized. The analysis betters both the theoretical knowledge of this kind of nozzle and the hydraulic phenomena occurring inside.