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Currently in automotive industrial, the emphasis on developing a better heat exchanger for vehicle thermal management is not only to address its functional performance but also its durability levels. One of the requirements for the latter is to test the heat exchanger in a simulated stone impact bench test with specified impact energy criteria. Due to various complex influence factors of this test, there is no existing simplified and physical-based relationship for heat exchanger design engineers to apply. With above considerations in mind and based on impact mechanical principles, impact heads configurations and heat exchangers geometrical details, this paper is proposing and developing a simplified impact mechanical models, where physical reasoned influence design factors can be presented and analyzed.

Soot fouling on exhaust gas recirculation coolers (EGRc) decreases thermal efficiency, implying the unfulfillment of NOx standards, and increases the pressure drop producing the malfunctioning of this device. The characterization of soot is of great interest since soot physico-chemical properties may have a direct influence on the degree of malfunctioning of EGRc. Thus, the combined analysis and interpretation of all the soot physico-chemical features are essential to correctly interpret its behavior when soot is deposited on the EGRc walls. In this context, the aim of this study is the characterization of five different types of diesel soot which were collected from several high pressure EGRc, working at different conditions (engine bench and vehicle). Each soot sample was characterized by means of elemental analysis, specific surface area (BET method), FESEM, FTIR, TGA, GC-MS and UV-visible spectroscopy.

The EASIS project clarified typology of dependent failures (Common Cause Failures, Common Mode Failures and Cascading Failures). Typology of dependent failures is a key concept used within safety standards such as IEC61508, or the on-going ISO26262. A presentation of this typology supported with concrete examples will be used to introduce a discussion on dependent failure analysis and bring in the distinction between the concepts of independence and absence of interference. Independence of EE architectural elements is required particularly between two architectural elements implementing a function and its associated safety mechanism. Absence of interference which is less demanding than independence is required to allow architectural elements of different criticality to cohabit (among others, safety-related elements and non-safety-related elements). Typical EE automotive examples will support this discussion

The transportation industry, and in particular the automotive industry is undergoing the effects of two major events: in 2008 the soaring price of oil and in 2009 the global economic crisis. In addition to these events, new regulations are being signed into law in many countries around the world to reduce, or at least control, CO2 emissions. In parallel, to respond to these challenges, automotive manufacturers and suppliers are developing the internal combustion engine along 3 major trends: Downsizing with integration of turbocharger or supercharger Hybridization : from micro hybrid to full hybrid Low-cost engine for the just required performance These new powertrain systems call for a growing number of combustion modes and separate controls, dependent of the operating point, to satisfy all functional and legislative requirements. Likewise, they require new components which are more and more complex and controllable with greater accuracy.

Electronic thermal management reduces pump and fan power consumption through gains in controllability and efficiency, and also provides for additional control of heat rejection management and variable control of coolant, oil, and engine temperatures. This paper represents the design, bench testing, and wind-tunnel vehicle testing of an advanced system comprised of an electric pump, electronic water flow proportioning valve, 42V alternator, 36V starter, and an electronic control system which commands the performance of the valve, pump, and fan clutch in relation to the cooling demand on a 1999 Volvo VN tractor equipped with a Cummins N14 engine. System design and test data are compared from both the stock cooling system and the advanced thermal management system (ATMS).

Considered in this study by the use of finite element model is a unit of assembled stator and one-way clutch (OWC) housed in a test setup, where the inner chamber is maintained at a given elevated temperature while its exterior housing surfaces are exposed to the room temperature. The two key components of dissimilar metals are assembled through the conventional interference fitting at their interface surfaces to form a friction joint at the room temperature. Due to the difference in the thermal expansion coefficients of two dissimilar materials, the outer component of aluminum from this joint tends to expand more than the inner component of steel when the temperature rises, thus leading to a possible relaxation in joining connection at their interface.

The control of sound fields radiated by vibrating structures in a passenger compartment, (especially structures connected to different organs like the engine powertrain, the fan motor unit, seats, the steering column, electrical motors more and more, etc.) is among the functions of the automotive manufacturers. The absence of physical prototypes in the development phase systems led OEMs1 to use tests results obtained on benches following technical specifications from manufacturers. The transition "bench to vehicle" for vibro- acoustic behaviour sets many challenges that this standard intends to clear up. This standard specifies the experimental method to transpose the dynamic forces generated by the global movements of an active component between the vehicle and a test bench. The efforts are first measured on test benches and then transposed from test bench towards the vehicle. The standard is now a French standard (XP R 19-701) and is submitted to ISO process [1].

With more emphasis on developing a better fuel-economic vehicle, applications of charged air cooler (CAC) in turbo charged gas and diesel engine plays an increasing critical role in both aspects of reduction of engine intake manifold temperature level and increase of intake air density. However, there is a limitation on how far charged air can be cooled when it starts to condensate within the charged air cooler (CAC). In this paper, staring from basic thermodynamics principles, a thermal flow model is developed and explains the physical reasons for the condensation generation inside charged air cooler (CAC) tubes.

In the near future the automotive industry shall introduce a wide range of new, high technological functions and applications. These are being driven by the industries demand for a reduction in fuel consumption, pollutant emissions and an overall improvement to vehicle safety. These new demands go together with the spread of electronics and the implementation of more and more electrically driven systems, with medium and high power capabilities. These electrically driven systems either replace previous hydro-mechanical systems, for Power Steering for instance, or allow for the introduction of new functionalities like engine “Start & Stop”. They can even lead to completely new power train architecture like hybrid vehicles for example. With all these systems the demand for more equipment with power electronics, tailored to the automotive industry, rises tremendously.

The implementation of the new electronic equipment makes the electrical and electronic architecture more and more complex. Thus technologies such as Power Line Communication constitute alternative solutions to reduce the number of wires and optimize the harness. Taking into account the know how and applications for household use, the power line communication feasibility in automotive domain had to be performed. This paper deals with the essential parameters to be identified in order to provide the appropriate power line modulation. Harness EMC behavior and EMI disturbances inside vehicle are developed in this paper.

The paper presents the Valeo approach to integrate the problem of recycling from the design stage. The first part deals with the reasons for which we have to design a recyclable unit, and in the second part, the technical solutions will be exposed.

To reduce the weight of the front windshield system, a fiber reinforced plastic design for the wiper arm and blade is being investigated. The use of suitable thermoplastics reinforced with short fiberglass allows the elaboration of good stiffness parts by injection moulding. Tests were carried out to show that stiffness depends on the fiberglass concentration and orientation. Likewise the temperature leads a decreasing of mechanical properties. Processing conditions of plastics have significant influence and aim to increase their performances, effectively a distribution in the orientation of fiberglass can be observed in the thermoplastic matrix. Various experimental means are used to characterise the plastic materials.

A two pedal drive device has been developped, using a standard dry clutch, an electric motor as an actuator and a microprocessor control. With the help of a compensator spring, a low power, low inertia motor with a fast response can be used. The control characteristic is basically a centrifugal law, with several modifications. Several sensors input information into the microprocessor and compensate for manufacturing tolerances and lining wear. The Electronic Clutch Control has been fitted to different cars and has given optimal results. It can be used in conjunction with manual transmissions, CVTs or other types of transmissions.

Technical improvements recently brought to the main components for trucks and commercial vehicles (turbochargers, alternators, brakes,...) are reviewed in the paper. In conclusion it is stated that researches conducted in the heavy commercial vehicles field play an important role in technical automotive progress.

The purpose of the 4-SPACE (4-Stroke Powered gasoline Auto-ignition Controlled combustion Engine) industrial research project is to research and develop an innovative controlled auto-ignition combustion process for lean burn automotive gasoline 4-stroke engines application. The engine concepts to be developed could have the potential to replace the existing stoichiometric / 3-way catalyst automotive spark ignition 4-stroke engines by offering the potential to meet the most stringent EURO 4 emissions limits in the year 2005 without requiring DeNOx catalyst technology. A reduction of fuel consumption and therefore of corresponding CO2 emissions of 15 to 20% in average urban conditions of use, is expected for the « 4-SPACE » lean burn 4-stroke engine with additional reduction of CO emissions.

Soot and NOx, may react in situ with each other and reduce, thus, their emissions. Therefore, this reaction can be considered as a strategy of elimination of both air pollutants at the same time. In general, it is well established that heterogeneous reactions between soot and the different gases, generally existent in combustion environments, are affected by soot properties. Detailed characterization of soot samples coupled to reactivity studies towards O2 and NO have been carried out in order to identify the differences and similarities among the kinds of soot studied for understanding in what extent the origin of soot samples is a key parameter on their structure and reactivity. The combined analysis and interpretation of the soot chemical-physical features are essential to correctly interpret and to predict its behavior in the combustion chamber when soot is in contact with the combustion gases at high temperature.

Using rivets to join the metal parts has always been commonplace, not only in aerospace but also in automotive industries. In order to have a rivet joint work properly upon assembly, It is a common practice that the rivet shank has to be radially expanded and fit tightly with the holes of the jointed components, under a great amount of pressing loads on it. When the stiffness around these holes is insufficient due probably to the design limitation, the deformation may be severe enough to induce high stresses on them. It is very beneficial to use numeric methods to simulate the riveting process and predict whether a rivet joint will be sustainable in the manufacturing process. In this work, analyzed is a specific type of riveted assembly in which its rivet hole is at the close proximity to the edge of plate. In addition, the material characteristics for the riveted plates with case hardening are accounted for by modeling them as bi-layered structures.

Presented here is the finite element modeling of plate-structures within which mechanical properties varied dramatically from their outer surfaces towards inside cores. Developing such a model representing what can be characterized as laminates is of great significance in accurately predicting the strength. The benefits of this proposed methodology will be discussed by case studies of a centrifugal pendulum that has gained its popularity in high-end passenger cars because of its superior vibration suppression. The system in this work is subject to an excessive and destructive load due to centrifugal forces at extremely high angular velocities. It can be shown that the inner core, with much softer mechanical properties, easily gets into the plastic state and significantly restrains it from continuing to carry more loads as the angular velocity is ramped up. Consequently, the outer layers have to take an increased share of loads and their stresses are significantly raised.

In embedded system software architectural design, the Real-Time (RT) behavior estimation needs special care and contains many technical challenges. Most of the current approaches depend on either the engineering judgment or the actual measurements that are performed during the integration-testing phase. Both approaches may cause errors that lead to violations in the RT constraints. Both approaches are not error proof and can yield to RT constraints violations discovered during simulation of RT architectural design or during product validation. Impact on project could even be a Central Processing Unit (CPU) change. In this work, Operating System (OS) process Execution Time (ET) is considered the basic element of RT architectural design. Each process ET is predicted based on previous software releases, using Machine Learning (ML) algorithms.

Engine ECU testing requires sophisticated sensor simulation and event capture equipment. FPGAs are the ideal devices to address these requirements. Their high performance and high flexibility are perfectly suited to the rapidly changing test needs of today's advanced ECUs. FPGAs offer significant advantages such as parallel processing, design scalability, ultra-fast pin-to-pin response time, design portability, and lifetime upgradability. All of these benefits are highly valuable when validating constantly bigger embedded software in shorter duration. This paper discusses the collaboration between Valeo and NI to define, implement, and deploy a graphical, open-source, FPGA-based engine simulation library for ECU verification.