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Engine cooling module air flows depend on package components and vehicle front end geometry. For years, in the early stages of vehicle development, front end geometry air flows were determined from 3/8 scale models or retrofit of similar existing vehicles. As time to market has become much shorter, finite element modeling of air flows is the only tool available. This paper describes how finite element simulations of front end air flows can be run early in the development program independent of any specific engine cooling module configuration and then coupled with traditional one-dimensional component performance models to predict cooling module air flows. The CFD simulation thus replaces the previous scale model testing process. The CFD simulations are used to determine the two parameters that characterize the front end geometry flow resistance (recovery coefficient and internal loss coefficient).

For over 30 years, field research and laboratory testing has consistently demonstrated that proper utilization of a seat belt dramatically reduces the risk of occupant death or serious injury in motor vehicle crashes. The injury prevention benefits of seat belts require that they remain fastened during collisions. Federal Motor Vehicle Safety Standards and SAE Recommended Practices set forth seat belt requirements to ensure proper buckle performance in accident conditions. Numerous analytical and laboratory studies have investigated buckle inertial release properties. Studies have repeatedly demonstrated that current buckle designs have inertial release thresholds well above those believed to occur in real-world crashes. Nevertheless, inertial release theories persist. Various conceptual amplification theories, coupled with high magnitude accelerations measured on vehicle frame components are used as support for these release theories.

Aerodynamic had played a primary role in high performance car since the late 1960s, when introduction of the first inverted wings appeared in some formulas. Race car aerodynamic optimisation is one of the most important reason behind the car performance. Moreover, for high performance car using naturally aspired engine, car aerodynamic has a strong influence also on engine performance by its influence on the engine airbox. To improve engine performance, a detailed fluid dynamic analysis of the car/airbox interaction is highly recommended. To design an airbox geometry, a wide range of aspects must be considered because its geometry influences both car chassis design and whole car aerodynamic efficiency. To study the unsteady fluid dynamic phenomena inside an airbox, numerical approach could be considered as the best way to reach a complete integration between chassis, car aerodynamic design, and airbox design.

Ford Motor Company is introducing “EcoBoost” gasoline turbocharged direct injection (GTDI) engine technology in the 2010 Lincoln MKS. A logical enhancement of EcoBoost technology is the use of E85 for knock mitigation. The subject of this paper is the optimal use of E85 by using two fuel systems in the same EcoBoost engine: port fuel injection (PFI) of gasoline and direct injection (DI) of E85. Gasoline PFI is used for starting and light-medium load operation, while E85 DI is used only as required during high load operation to avoid knock. Direct injection of E85 (a commercially available blend of ∼85% ethanol and ∼15% gasoline) is extremely effective in suppressing knock, due to ethanol's high inherent octane and its high heat of vaporization, which results in substantial cooling of the charge. As a result, the compression ratio (CR) can be increased and higher boost levels can be used.

A compact and high performance electric motor, called the 3D motor and designed to achieve output torque density of 100 Nm/L, was developed for use on electric vehicles and hybrid electric vehicles. The motor adopts an axial flux configuration, consisting of a disk-shaped stator sandwiched between two disk-shaped rotors with permanent magnets. It also adopts 9-phase current with a fractional slot combination, both of which increase the torque density. The rated torque output of this high power-density motor is achieved by applying a hybrid cooling system comprising a water jacket on the outer case of the stator and oil dispersion into the air gaps. The mechanical strength of the rotors against centrifugal force and that of the stator against torque exertion were confirmed in mechanical experiments. Several measures such as flux barriers, a chamfered rotor rim, parallel windings, and radially laminated cores were adopted to suppress losses.

The cost of human natural language translation of Service Information, Assembly Instructions, Training Materials, Operator Manuals and other similar documents is a major expense for manufacturers. One translation avoidance method involves replacing most of a document’s text with still and/or animated graphics. While the graphics with minimum text concept has savings potential, clarity of communication must be maintained for widespread application of this technique. The necessary clarity should be achieved if standards are established for the symbols and graphical conventions used. This paper provides an example of a repair procedure documented using the graphics with minimum text paradigm, describes many of the anticipated standards and provides an update on the progress towards achieving a standard development project.

The timing and associated levels of braking between initial brake pedal application and actual maximum braking at the wheels for a tractor-semitrailer are important parameters in understanding vehicle performance and response. This paper presents detailed brake timing information obtained from full scale instrumented testing of a tractor-semitrailer under various conditions of load and speed. Brake timing at steer, drive and semitrailer brake positions is analyzed for each of the tested conditions. The study further seeks to compare the full scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models available in commercial software packages in order to validate the model's brake timing parameters. The brake timing data was collected during several days of full scale instrumented testing of a tractor-semitrailer performed at the Transportation Research Center, in East Liberty, Ohio.

A driving simulator capable of duplicating the critical sensations incurred during a spin, or when a driver is engaged in drift cornering, was constructed by Mitsubishi Heavy Industries, Ltd., and Hiromichi Nozaki of Kogakuin University. Specifically, the simulator allows independent movement along three degrees of freedom and is capable of exhibiting extreme yaw and lateral acceleration behaviors. Utilizing this simulator, the control characteristics of drift cornering have become better understood. For example, after a J-turn behavior experiment involving yaw angle velocity at the moment when the drivers attention transitions to resuming straight ahead driving, it is now understood that there are major changes in driver behavior in circumstances when simulator motions are turned off, when only lateral acceleration motion is applied, when only yaw motion is applied, and when combined motions (yaw + lateral acceleration) are applied.

Extenics is a new cross discipline to study rules and methods of solving contradictory problems in the real world. The basic concepts and theoretical frame of extenics are briefly introduced in this paper. Based on the merit of extenics, the extension evaluation method was applied to evaluate the brake materials according to a five-grade criterion established in this study. Considering the results computed by the original and simplified models, the similar conclusions were made: all four brake samples, marked A - D, were evaluated in the first grade based on the calculated dependence degrees, and sample B was judged as the best performing friction material with the highest dependence degree and the lowest wear rate.

Cavitation in the nozzles of various shapes and liquid jets discharged from the nozzles are visualized using a high-speed camera to investigate the effects of cavitation on liquid jet deformation. Cylindrical nozzles and two-dimensional (2D) nozzles of various upstream diameters and length-to-diameter ratios (L/D) are used. For simultaneous high-speed visualizations of cavitation and a jet, a tilted acrylic plate is placed in front of the jets injected through the 2D nozzles, while three mirrors are used to capture both the front view of the jet injected through a cylindrical nozzle and the side view of cavitation. The visualizations confirm that the collapse of a cavitation cloud near the exit induces a ligament formation in 2D and cylindrical nozzles of various L/Ds. Although no vapor film is formed in short nozzles, cavitation clouds are shed near the exit and induce ligaments.

The investigation of vehicle performances under on-road conditions has been required for emission reduction and energy saving in the real world. In this study, Real Car Simulation Bench (RC-S) was developed as an instrument for actual vehicle bench tests under on-road driving conditions, which could not be performed by using conventional chassis dynamometer (CH-DY). The experimental results obtained by RC-S were compared with the on-road driving data on the same car as used in RC-S tests. As a result, it was confirmed that RC-S could accurately reproduce the behavior of fuel consumption and exhaust emissions under on-road driving conditions.

Building on two decades of expertise, a fourth generation fleet test protocol is presented for assessing the response of engine performance to gasoline additive treatment. In this case, the ability of additives to remove pre-existing deposit from the intake systems of port fuel injected vehicles has been examined. The protocol is capable of identifying real benefits under realistic market conditions, isolating fuel performance from other effects thereby allowing a direct comparison between different fuels. It is cost efficient and robust to unplanned incidents. The new protocol has been applied to the development of a candidate fuel additive package for the North American market. A vehicle fleet of 5 quadruplets (5 sets of 4 matched vehicles, each set of a different model) was tested twice, assessing the intake valve clean-up performance of 3 test fuels relative to a control fuel.

In 2005, the growing emphasis on fuel efficiency coupled with the long-recognized negative effects of viscous friction caused by engine hydrodynamic lubrication, led to considerations of the benefits of lower viscosity engine oils by the SAE Engine Oil Viscosity Classification (EOVC) Task Force. More recently these considerations were given further impetus by OEM enquiry regarding modification of the SAE Viscosity Classification System to include oils of lower viscosity specification than that of SAE 20. For the EOVC Task Force, such considerations of commercially available, significantly lower viscosity engine oils, also produced a need to reassess the precision of high shear rate viscometry of such engine oils as presently practiced at 150°C - as well as interest in temperatures such as 100° and 120°C believed more representative of engine operating conditions.

Today's automotive and electronics technologies are evolving so rapidly that educators and industry are both challenged to re-educate the technological workforce in the new area before they are replaced with yet another generation. In early November 2009 Ford's Product Development senior management formally approved a proposal by the University of Detroit Mercy to transform 125 of Ford's “IC Engine Automotive Engineers” into “Advanced Electric Vehicle Automotive Engineers.” Two months later, the first course of the Advanced Electric Vehicle Program began in Dearborn. UDM's response to Ford's needs (and those of other OEM's and suppliers) was not only at the rate of “academic light speed,” but it involved direct collaboration of Ford's electric vehicle leaders and subject matter experts and the UDM AEV Program faculty.

Virtual testing is a method that simulates lab testing using multi-body dynamic analysis software. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The disadvantage is that accurate specimen models are sometimes hard to obtain since nonlinear components such as tires, bushings, dampers, and engine mounts are hard to model. Therefore, virtual testing accuracy varies significantly. The typical virtual rigs include tire and spindle coupled test rigs for full vehicle tests and multi-axis shaker tables for component tests. Hybrid simulation combines physical and virtual components, inputs and constraints to create a composite simulation system. Hybrid simulation enables the hard to model components to be tested in the lab.

Advanced High Strength Steels (AHSS) have been implemented in the automotive industry to balance the requirements for vehicle crash safety, emissions, and fuel economy. With lower ductility compared to conventional steels, the fracture behavior of AHSS components has to be considered in vehicle crash simulations to achieve a reliable crashworthiness prediction. Without considering the fracture behavior, component fracture cannot be predicted and subsequently the crash energy absorbed by the fractured component can be over-estimated. In full vehicle simulations, failure to predict component fracture sometimes leads to less predicted intrusion. In this paper, the feasibility of using computer simulations in predicting fracture during crash deformation is studied.

In this paper, we present a parameter-free, or a node-based optimization method for finding the smooth optimal free-form of automotive shell structures, including global and local curvature distributions such as beads or embossed ribs. The design problems dealt with in this paper involve a stiffness problem. Stiffness is maximized using the compliance as an objective functional. The optimum design problem is formulated as a distributed-parameter, or non-parametric, shape optimization problem under the assumptions that the shell is varied in the normal direction to the surface and the thickness is constant. The shape gradient function and the optimality conditions are then theoretically derived. The optimum free-form, or optimal curvature distribution, is determined by applying the derived shape gradient function in the normal direction to the shell surface as pseudo external forces to vary the surface and to minimize the objective functional.

A new index U* for evaluating load path dispersion is proposed, using a structural load path analysis method based on the concept of U*, which expresses the connection strength between a load point and an arbitrary point within the structure. U* enables the evaluation of the load path dispersion within the structure by statistical means such as histograms and standard deviations. Different loading conditions are applied to a body structure, and the similarity of the U* distributions is evaluated using the direction cosine and U* 2-dimensional correlation diagrams. It is shown as a result that body structures can be macroscopically grasped by using the U* distribution rather than using the stress distribution. In addition, as an example, the U* distribution of torsion loading condition is shown to comprehensively include characteristics of the U* distribution of other loading conditions.

As mass reduction becomes an increasingly important enabler for fuel economy improvement, having a robust structural development process that can comprehend Vehicle Dynamics-specific requirements is correspondingly important. There is a correlation between the stiffness of the body structure and the performance of the vehicle when evaluated for ride and handling. However, an unconstrained approach to body stiffening will result in an overly-massive body structure. In this paper, the authors employ loads generated from simulation of quasi-static and dynamic vehicle events in ADAMS, and exercise structural finite element models to recover displacements and deflected shapes. In doing so, a quantitative basis for considering structural vehicle dynamics requirements can be established early in the design/development process.

Accident statistics shows pedestrian accident fatalities as one of the important concerns globally. In view of this, new test protocols for pedestrian safety have been drafted in regulation as well as in consumer group. Also as per new ENCAP requirements, pedestrian safety assessment is used as one of the four assessment criteria's (Adult protection, child safety, pedestrian safety, safety assist) in deciding the overall vehicle safety. Hence today importance of pedestrian safety is perceived as never before in vehicle development program. Basically pedestrian safety evaluation involves subsystem level (head form, upper leg form and lower leg form) impact tests representing human body parts, at specific region on test vehicle with injury limits to decide the severity of impact. In general these injuries are governed by vehicle styling, vehicle stiffness, hard points clearances from vehicle exterior like bonnet, bumper etc.