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Fuel and air behavior in the induction passage of a 4-valve engine were investigated in order to improve response at low and medium engine speeds. It was found that response is affected not only by wall vetting but also by fuel being pushed back into the intake manifold and by a lack of fuel which occurs during the transient. Futhermore, fuel-air mixing was found to be insufficient at certain injection timings, resulting in poor combustion and a consequent increase in exhaust emission and fuel consumption. This paper describes the factors of the fuel injection system which are critical for optimum response. Recommendations are made for injector location and injection timing and a proposal is put forward for a system of compensatory fuel injection to improve combustion efficiency during acceleration.

To assess the ability of a material to create filler metal flow and fill the brazing joint areas during the brazing process, we adapted a method which is called aluminum Flow Factor test. The target is to take benefit of this test in order to reach an optimum level of heat exchanger performance from project development steps. This paper studies similar aluminum clad material compositions coming from different suppliers. After brazing process, significant differences were noticed in the filler metal flow results. This study highlighted the impact of brazing peak temperature to create more or less flow of filler metal. The Flow Factor is promoted by the increase of brazing peak temperature. It also showed that regardless the material gage, at a low peak temperature of 591°C, Flow Factor are quite similar around 0,18.

Diesel will continue to be an indispensable energy carrier for the car fleet CO2 emission targets in the short-term. This is particularly relevant for heavy-duty vehicles as for mid-size cars and SUVs. Looking at the latest technology achievements on the after-treatment systems, it can be stated that the concerning about the NOx emission gap between homologation test and real road use is basically solved, while the future challenge for diesel survival is to keep its competitiveness in the CO2 vs cost equation in comparison to other propulsion systems. The development of the combustion system design still represents an important leverage for further efficiency and emissions improvements while keeping the current excellent performance in terms of power density and low-end torque.

The diesel biodiesel-diesel oil-bioethanol mixture displays real potential uses as an alternative fuel. The idea stands on the fact that a series of properties of the two biofuels complete each other. Therefore, in this study, biodiesel and bioetanol were blended with commercial diesel fuel at 5%, 10%, 15%, 20% and 25% and 30% on a volume basis to characterize the key fuel properties of the blends such as density, viscosity, surface tension, lubricity, flash point and cold filter plugging point. The densities of the diesel oil-biodiesel-bioethanol blends are in the range of 841-852 kg/m3, very close to the diesel fuel requirement related in EN 590. In the case of the investigated blends kinematic viscosity is in the range of 2.176…2.756 mm2/s. The blends flash points that containing 5% ethanol are in the range of 16…18 °C, and which containing 10% ethanol are less than 16 °C. Measured values of surface tensions are in the range of 28.47…34.83 mN/m.

In the paper, the Flat Plank Tire Tester of Changchun Automobile Institute is introduced. This paper, according to practical experiences, generalizes some issues in the tire's non-steady state test. In the non-steady state test, it must be assured that the footprint centerline of tire coincides with that of slid platform, which guarantees no sliding motion between tire and slid platform during the movement. Due to tire taper effect and inhomogeneous tire material, when its side slip angle is zero, side force and aligning torque are not zeros, but have initial values. Here two approaches are discussed to eliminate the side force and aligning torque. Besides, other factors in the test are put forward for discussion. Eliminating the interference can obviously improve the test accuracy. This paper also provides test curves of both pure side slip angle input and pure yaw angle input.

EcoCAR 2: Plugging In to the Future (EcoCAR) is North America's premier collegiate automotive engineering competition, challenging students with systems-level advanced powertrain design and integration. The three-year Advanced Vehicle Technology Competition (AVTC) series is organized by Argonne National Laboratory, headline sponsored by the U. S. Department of Energy (DOE) and General Motors (GM), and sponsored by more than 28 industry and government leaders. Fifteen university teams from across North America are challenged to reduce the environmental impact of a 2013 Chevrolet Malibu by redesigning the vehicle powertrain without compromising performance, safety, or consumer acceptability. During the three-year program, EcoCAR teams follow a real-world Vehicle Development Process (VDP) modeled after GM's own VDP. The VDP serves as a roadmap for the engineering process of designing, building and refining advanced technology vehicles.

It is well known that high ethanol content fuels have to face poor quality regarding startability in cold conditions on a spark ignited engine. This paper will show test results when using E0, E85 and E100 fuels led on a single cylinder engine equipped with an active valve train research system. In order to improve engine behavior in severe thermal conditions, influence of several parameters was investigated. Injection strategies (timing, split injection, flow rate), valve train laws (delayed intake opening, valve lift…), ignition parameters (timing, multi-spark, strong energy coil…) as well as intake pressure were analyzed thanks to cylinder pressure analysis and specific test procedure. CFD investigations (influence of fuel, wall wetting) helped us to confirm some hypothesis on physical phenomenon. Those simulations were correlated with spray and wall film visualizations in the inlet port on an optical engine.

Many questions have been directed in recent years to aircraft structural repair communities concerning bonded repairs. Areas of concern have primarily focused on surface preparation issues with the various types of composite and metallic structure, cure profiles, and quality assurance requirements. These questions have come from a variety of sources – within the OEM, from outside suppliers and from customers, both military and commercial. Some questions are asked in an effort to reduce the “down time” on an aircraft associated with these repairs. Others because of frequent “re-repairs” due to poor bond quality from a previous repair. Future design concepts are focusing on more “one-piece” types of structure that will rely on structural, durable repairs that can be performed with a minimal amount of facilities required.

The next generation of automotive engines has to meet 2004 emission limits, ideally with improved fuel economy and with noise emission which is at least 3 dBA below the current status. Using both simulation and experimental analysis these challenging requirements can only be fulfilled by clearly defining all key steps in NVH development and by applying suitable technological methods. The development procedure discussed in this paper is characterised by several aspects: two stage prediction procedure fully integrated in the design process, combustion development with a definite focus on noise, a closed loop between simulation and test bed development and consideration of noise in the calibration of engine and drivetrain management systems. Apart from meeting target noise levels, noise quality is the reference parameter which is continuously evaluated by means of the AVL Annoyance Index.

Electrical vertical takeoff and landing (eVTOL) vehicles for urban air mobility (UAM) are garnering increased attention from both the automotive and aerospace industries, with use cases ranging from individual transportation, public service, cargo delivery, and more. Distributed electric propulsion systems are their main technical feature; they determine vehicle size and propulsion efficiency and provide distributed thrust to achieve attitude control. Considering the intended role of eVTOL vehicles, ducted-fan systems are ideal choice for the propulsor, as the duct provides a physical barrier between the rotating blades and the human, especially during the take-off and landing phases. Key Technology Challenges of Electric Ducted Fan Propulsion Systems for eVTOL introduces the main bottlenecks and key enablers of ducted-fan propulsion systems for eVTOL applications.

Operating procedures for keyboard data entry in avionics are analyzed. The type of information being entered may be identified either before or after entry of the alphanumeric characters. The keys which are used to identify the type of data may be collected in a centralized control unit or distributed throughout the cockpit adjacent to the associated displays. The Collins NCS-31 and the King KCU 565 navigation and control systems are discussed as illustrations of two sets of choices for operating procedures. Emphasis is placed upon correspondence between the thought processes associated with data entry and the pilot's actions in entering data.

Inter-vehicle communication is being considered as a means for increasing safety and efficiency in future intelligent highways. However, the security in these future mobile ad hoc networks of vehicles should not be an after thought. The main challenges in developing such security schemes are the highly dynamic environment and the cost restrictions. In this paper, we propose a keyless scheme for message authentication in inter-vehicle communication by verifying the sender’s position and velocity. The approach relies on signal propagation time to authenticate messages being communicated. No infrastructure or dedicated hardware beyond standard GPS is required.

The world today is moving more towards convenience and luxury. Auto manufacturers are being constantly challenged to provide innovative additions to conventional vehicles in terms of attractive features. This paper describes one such invention proposed to add convenience and novelty to the use of two wheelers. The proposed system is called a “Keyless Scooter”. Derived from the idea of keyless entry in four wheelers, the system aims at extending this luxury to a larger band of population in India, i.e. users of two wheeled vehicles. The system eliminates use of a mechanical lock and key arrangement. All functions carried out by the mechanical arrangement of lock and key are replaced with an equivalent electronic system. A “Keyless Scooter” is one in which a user can just approach it with a key fob on himself/herself and start the vehicle, open the luggage box, etc. without having to insert a key physically into the lock body.

Just-In-Time processing is changing the way the automotive industry operates. This paper explains Just-In-Time systems, how they are being applied at General Motors, and how the U.S. auto industry is applying them. The paper is based on three main premises: 1) the design of the product and the design of the process must be integrated, 2) the construction process is critical, and 3) the first day of operation of the process must be the first day efforts are made to improve it.

This Keynote Address compares the deterministic design methodology, which is being used predominantly currently, with the probabilistic design methodology which enables the designer to design components to a desired reliability goal at a desired confidence level. It is demonstrated that the probabilistic design-by-reliability methodology is more economical plus it assures that there will be fewer product failures, fewer product recalls and more satisfied customers. It is urged that, henceforth, this design-by-reliability methodology be taught in our Colleges of Engineering instead of the inefficient deterministic one.

Dating from the early 1980s, Knowledge-Based Engineering technology (KBE) has been used to capture and automate design and engineering, in particular in the automobile and aircraft industries. A viable KBE system in the 21st century must provide users with a dynamic modeling feedback loop in an environment favorable to both exploration and experimentation, supplying various approaches for engineering a given set of artifacts. The fundamental properties of a KBE system must include automatic caching and dependency tracking for the scalable runtime performance of large models, minimal source code volume, and efficient and rapid tools for model development and debugging. And, not least, it must complement existing CAD systems. A crucial aspect of a bonafide KBE system is its language-based core, embedded in a standardized, full-featured programming language, i.e., as a superset.

After a somewhat unsuccessful birth, air starting has proved to be an efficient, low cost method of starting diesel engines in cold weather. Despite the problems of poor installation, bad connections, under-capacity tanks, and water in the air, steps can be taken to ensure the system's success. This paper analyzes the problems and merits of the air starting system and presents specific suggestions on ways to minimize or eliminate the difficulties involved in its implementation. The attendant problems of noise level and consumer education are discussed. Suggestions for the maintenance of air starting systems are included.

Frequently, new design efforts have successfully used DFMA techniques in order to yield designs that are simpler and faster to assemble, easier to maintain, and less costly than designs that utilized the previous philosophy of several small parts being mechanically fastened together. However, a substantial difference exists between using DFMA on a new program, such as the F/A-18E/F Super Hornet or the Joint Strike Fighter, and using DFMA on an existing production program such as the F-1 5 Eagle or the C-17 Globemaster III. Generally, design efforts on a new program would be funded under that particular program's development costs. However, for an existing program where the program life is limited, it becomes more challenging to implement DFMA techniques to new redesigns since the return on investment (ROI) and break-even point are directly proportional to the expected life cycle savings and implementation costs.

Spray-guided gasoline direct injection SI engines attract as one of new generation lean-burn engines to promise CO2 reduction. These typically adopt “narrow-spacing” concept in which an injector is centrally mounted close to a spark plug. Therefore, geometric targets of the fuel spray and a position of the spark plug have to be exactly limited to maintain a proper mixture in the spark gap. In addition, the stable combustion window is narrow because the spark ignition is limited in a short time during and immediately after the injection. These spatial and temporal restrictions involve some intractable problems concerning the combustion robustness due to the complicate phenomena around the spark plug. The local mixture preparation near the spark plug significantly depends on the spray-induced charge motion. The intense flow induced by the motion blows out and stretches the spark, thereby affecting the spark discharge performance.

The objective of the study was to investigate the spray and combustion characteristics of Jet Propellant-8 (JP-8) using a high-pressure fuel injector which is capable of up to 250-MPa fuel injection pressure. Experiments were performed in a constant-pressure flow-through combustion chamber at the ambient conditions of 825 K and 6 MPa for the oxygen concentration of 0 and 21%. JP-8 was injected over a range of fuel injection pressures from 50 to 250 MPa for single injection events to establish a baseline operation. Pilot and post injections were used to study the effect of multiple injections on spray and combustion of the high-pressure fuel injector. Both pilot and post injection separation times and quantities were systematically varied. JP-8 spray and combustion events were imaged at 75 kHz using a combination of Mie scattering and OH* chemiluminescence imaging.