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This paper focuses on full body dynamical analysis of car ingress/egress motion. It aims at proposing an experimental protocol adapted for analysing joint loads using inverse dynamics. Two preliminary studies were first performed in order to 1/ define the main driver/car interactions so as to allow measuring the contact forces at all possible contact zones and 2/ identify the design parameters that mainly influence the discomfort. In order to verify the feasibility of the protocol, a laboratory study was carried out, during which two subjects tested two car configurations. The experimental equipment was composed of a variable car mock-up, an optoelectronic motion tracking system, two 6D-force plates installed on the ground next to the doorframe and on the car floor, a 6D-Force sensor between the steering wheel and the steering column, and two pressure maps on the seat. Motions were reconstructed from measured surface markers trajectories using inverse kinematics.

This paper summarizes the Fast Fourier Transform (FFT) methodology, special equipment, set-up and testing that is recommended to properly characterize the surface of bearing journals that will not result in objectionable noise or vibration. Traditional surface profiles and finish callouts do not capture some of the key characteristics for addressing what is often the customer's greatest complaint, noise. Noise can vary based on the sensitivity of the vehicle but understanding how to accurately describe (design, test, and measure) a surface for a given vehicle can result in an optimized design and reduce process time during manufacturing. Furthermore, this paper will recommend techniques for determining the proper limits of the FFT callouts.

An ignition delay correlation was developed for a toluene reference fuel (TRF) blend that is representative of automotive gasoline fuels exhibiting two-stage ignition. Ignition delay times for the autoignition of a TRF 91 blend with an antiknock index of 91 were predicted through extensive chemical kinetic modeling in CHEMKIN for a constant volume reactor. The development of the correlation involved determining nonlinear least squares curve fits for these ignition delay predictions corresponding to different inlet pressures and temperatures, a number of fuel-air equivalence ratios, and a range of exhaust gas recirculation (EGR) rates. In addition to NO control, EGR is increasingly being utilized for managing combustion phasing in spark ignition (SI) engines to mitigate knock. Therefore, along with other operating parameters, the effects of EGR on autoignition have been incorporated in the correlation to address the need for predicting ignition delay in SI engines operating with EGR.

The challenge for decreasing the emissions of compression ignition engines now remains mainly on NOx control. If the Lean NOx Trap (LNT) and Selective Catalytic Reduction by Urea (Urea-SCR) are very efficient, their extra-cost and management are a major issue for the OEMs. In that context, the selective catalytic reduction by hydrocarbons (HC-SCR) appears to be an interesting alternative solution, with a more limited NOx conversion efficiency but an easier packaging (diesel fuel as a reductant) and a limited price (reasonable coating cost / no PGM). In the framework of the RedNOx project, a prototype catalyst made of 2% silver on Alumina coated on cordierite was manufactured and tested on a synthetic gas bench. In parallel, an exhaust implementation study has been led to ensure the most suited conditions for injection. Thanks to SGB and simulation results, adapted engine tests have been designed and performed.

The double linear damage model developed by Manson and Halford helps to determine the knee point, which is the intersection between the two straight lines. The damage to the component is then calculated based on this knee point. The new approach mentioned in this paper helps to evaluate the damage on the component in a slightly different way. It uses the knee points as mentioned by Manson and Halford and decomposes the damage to the component for Phase I & Phase II. It then uses the equivalent damage approach and establishes the damage to the component. This will be explained with an example.

This paper presents how a 1D engine simulation tool can be used in the optimization process of a naturally aspirated spark-ignition engine, evaluating the vehicle acceleration performance through engine-vehicle coupling model based. The main objective is to compare two engine configurations, one focusing on the high torque at low speeds and the other focusing on high power at high speeds, with a baseline one. Later on the two configurations were compared in order to choose the best one to be implemented in the automotive market. The main steps and data used for the model validation and performance improvements through simulation and model-based optimization are described in the paper. As final results, the vehicle acceleration time was decreased and the maximum vehicle speed was increased in comparison with the baseline configuration.

Advanced High-Strength Steels (AHSS) have become an essential part of the lightweighting strategy for automotive body structures. The ability to fully realize the benefits of AHSS depends upon the ability to aggressively form, trim, and pierce these steels into challenging parts. Tooling wear has been a roadblock to stamping these materials. Traditional die materials and designs have shown significant problems with accelerated wear, galling and die pickup, and premature wear and breakage of pierce punches. [1] This paper identifies and discusses the tribological factors that contribute to the successful stamping of AHSS. This includes minimizing tool wear and galling/die pick-up; identifying the most effective pierce clearance (wear vs. burr height) when piercing AHSS; and determining optimal die material and coating performance for tooling stamping AHSS.

Scuffing is one of the major problems that influence the life cycle and reliability of several auto components, including engine cylinder kits, flywheels, camshafts, crankshafts, and gears. Ferrous casting materials, such as gray cast iron, ductile cast iron and austempered ductile cast iron (ADI) are widely applied in these components due to their self-lubricating characteristics. The purpose of this research is to determine the scuffing behavior of these three types of cast iron materials and compare them with 1050 steel. Rotational ball-on-disc tests were conducted with white mineral oil as the lubricant under variable sliding speeds and loads. The results indicate that the scuffing initiation is due to either crack propagation or plastic deformation. It is found that ADI exhibits the highest scuffing resistance among these materials.

The modeling of turbulent combustion is a crucial problem for the numerical simulation of flames and combustion chambers. In this paper turbulent combustion is discussed with a lagrangian model which is useful to study turbulent combustion problems. A coupling between this lagrangian model and a presumed pdf method is used with complex chemistry. The validation of the kinetic mechanism was studied before integrating it in the computer code for reciprocating engines. The results of computations with the present model are compared with the experimental results obtained from experiences obtained in our laboratory and from PSA engine. These comparisons between modeling and experiments show a good agreement.

The development process of a water pump impeller used on a sport utility vehicle engine is described. A review of the design process is presented in this paper including the computer-aided flow analysis together with testing procedures. By computer modeling, one can estimate the coolant flow characteristics of a given impeller blade shape for providing increased cooling performance and improved efficiency on the engine. It also provides directions for the improved design. The test data are used specifically to confirm the analysis results.

In an effort to improve the dent resistance of exterior body panels at reduced steel thicknesses, some automobile manufacturers have pursued the application of bake hardenable steels. Unfortunately, bake hardenable steels have only been available as cold rolled or with electro-zinc or electro zinc/iron coatings. This situation has been a deterrent for those automobile manufacturers that prefer the use of hot dip galvanneal coatings. Recently, the interest in hot dip galvanneal bake hardenable steels has led to the investigation and development of this more advanced steel grade. This paper presents the results of a stamping trial and dent testing on three exposed hot dip galvannealed materials; i) Regular Ultra Low Carbon (ULC), ii) Rephosphorized ULC, and iii) Rephosphorized Bake Hardenable ULC steel.

At the end of four years Research & Development programme, the bench test results for the MCE-5 VCR engine are presented. Downsized supercharged Variable Compression Ratio engines allow for a 30% fuel consumption reduction while providing high power and torque and opening the way to numerous pollutants emissions reduction strategies. In this context, piston to crankshaft transmission by means of gears gives new opportunities for future mass production of rigid and robust low friction engines that conform to VCR requirements while improving piston and rings operation. Through development programmes, the MCE-5 gear-based compression ratio control device proved its robustness and reliability, as well as its ability to allow the design of compact and efficient VCR engines which are easy to integrate into all vehicles.

Today, some vehicles include a regenerative-braking system such as the electrical motor-generator that converts the vehicle's kinetic energy into electrical energy to recharge one or more vehicle batteries. The idea is to use air flow to produce additional electrical energy in response to deceleration of the vehicle. With the Wind Power Generator System (WPGS) as a green system, a vehicle can produce extra energy, reduce gasoline usage, and reduce air pollution.