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Many different studies have been performed to understand brake roughness, and in particular how brake rotor Disc Thickness Variation (DTV) is generated. The intent of this paper is to analytically explore through non- linear finite element modeling methods the effects of wheel joint variables on brake rotor mounted Lateral RunOut (LRO). The phenomenon of LRO is believed to be a primary contributor to DTV generation and resulting brake roughness. CAE analyses were conducted in non-linear contact mechanics in which real contacts between components exist. Various joint designs were simulated to compare rotor LRO and coning. Several parameters inherent to the design of wheel joints were varied and studied. A comparative approach was used to develop specific design recommendations for LRO reductions.

A 2D model for vehicle-to-vehicle impact analysis that was presented in an earlier paper [1], has been used to study several two-vehicle frontal impacts with different incidence angles, frontal overlap offsets, and mass ratios. The impacts have been evaluated in terms of energy and momentum change in the bullet vehicle and the target vehicle. Based on comparisons between pre- and post-impact longitudinal, lateral, and angular components of kinetic energy, and linear and angular momenta, the impacts experienced by the target vehicle and the bullet vehicle have been classified as collinear or oblique. These results have been used to propose a definition of frontal impact based on vehicle kinematics during a crash.

A data processing algorithm is presented for determining the spatial orientation and position of a rigid body in impact tests based on an instrumentation scheme consisting of a triaxial angular rate sensor and a trialaxial linear accelerometer. The algorithm adopts the unit quaternion as the main parameterized representation of the spatial orientation, and calculates its time history by solving an ordinary differential equation with the angular rate sensor reading as the input. Two supplemental representations, the Euler angles and the direction cosine matrix, are also used in this work, which provide an intuitive description of the orientation, and convenience in transforming the linear accelerometer output in the instrumentation frame to the global frame. The algorithm has been implemented as a computer program, and a set of example impact tests are included to demonstrate its application.

The intake and exhaust port design plays a substantial role in performance of combustion systems. The port design determines the volumetric efficiency and in-cylinder charge motion of the spark-ignited engine which influences the thermodynamic properties directly related to the power output, emissions, fuel consumption and NVH properties. Thus intake port has to be appropriately designed to fulfill the required charge motion and high flow performance. While turbulence intensity and air-mixture quality affect dilution tolerance and fuel economy as a result, breathing ability affects wide open throttle performance. Traditional approaches require experimental techniques to reach a target balance between the charge motion and breathing capacity. Such techniques do not necessarily result in an optimized solution.

This paper is the fifth in the series of documents designed to identify the progress on the SAE Plug-in Electric Vehicle (PEV) communication task force that follows 2010-01-0837, 2011-01-0866, 2012-01-1036 and 2013-01-1475. The primary focus of this paper is to discuss the most recent revision of J2847/1 [1], which deals with Smart Charging applications, plus the initial release of J2847/3 [2], which can be thought of as dealing with “Smart Discharging” applications. Both documents are based on the use of the Smart Energy Profile 2.0 (SEP2) Application Protocol Standard (V1.0) which was completed by the ZigBee Alliance in April 2013. The standard was then accepted by the IEEE and subsequently released as IEEE 2030.5 [3]. SEP2 started with a Marketing Requirements Document (MRD) that J2836/1™ [4]expanded for the automotive Use Cases for Smart Charging, The MRD was then used to generate the SEP2 Technical Requirements Document (TRD) that set the automotive requirements in J2931/1 [5].

This paper highlights a simplified CAE model technique, which can simulate and predict door crush strength performance quickly. Such quick models can be used for DFSS and Design change studies. The proposed method suggests an equivalent sub model technique using only the door beam with tuned stiffness end springs to predict FMVSS214S full vehicle crush performance. Such models can be solved in minutes and hence very useful for DFSS studies during product design. The proposed method can be used to finalize door beam design for identical size of vehicle doors to meet required FMVSS214S crush performance. The paper highlights the door beam end springs tuning for identical size of cars and SUVs. Four vehicles were considered for the study. A single spring F-D (force -displacement) is tuned which correlated well for frond door of all the four vehicles. A separate unique spring F-D was needed which correlated well for rear door of all the 4 vehicles.

The introduction of tumble into the combustion chamber is an effective method of enhancing turbulence intensity prior to ignition, thereby accelerating the burn rates, stabilizing the combustion, and extending the dilution limit. In this study, the primary intake runners are partially blocked to produce different levels of tumble motion in the cylinder during the air induction process. Experiments have been performed with a Chrysler 2.4L 4-valve I4 engine at maximum brake torque timing under two operating conditions: 2.41 bar brake mean effective pressure (BMEP) at 1600 rpm, and 0.78 bar BMEP at 1200 rpm. A method has been developed to quantify the tumble characteristics of blockages under steady flow conditions in a flow laboratory, by using the same cylinder head, intake manifold, and tumble blockages from the engine experiments.

With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

In-cylinder charge motion is known to significantly increase turbulence intensity, accelerate combustion rate, and reduce cyclic variation. This, in turn, extends the tolerance to exhaust gas recirculation (EGR), while the introduction of EGR results in much lowered nitrogen oxide (NOx) emissions and reduced fuel consumption. The present study investigates the effect of charge motion in a spark ignition engine on fuel consumption, combustion, and engine-out emissions with stoichiometric and EGR-diluted mixtures under part-load operating conditions. Experiments have been performed with a Chrysler 2.4L 4-valve I4 engine under 2.41 bar brake mean effective pressure at 1600 rpm over a spark range around maximum brake torque timing. The primary intake runners are partially blocked to create different levels of tumble, swirl, and cross-tumble (swumble) motion in the cylinder before ignition.

Tuned mass dampers (TMDs) or vibration absorbers are widely used in the industry to address various NVH issues, wherein, tactile-vibration or noise mitigation is desired. TMDs can be classified into two categories, namely, tuned-to-resonance and tuned-to-discrete-excitation. An overwhelming majority of TMD applications found in the industry belong to the tuned-to-resonance category, so much of information is available on design considerations of such dampers; however, little is published regarding design considerations of dampers tuned-to-discrete-excitation. During this study, a problem was solved that occurred at a discrete excitation frequency away from the primary resonance frequency of a steering column-wheel assembly. A solution was developed in multiple stages. First the effects of various factors such as mass and damping were analyzed by using a closed-form solution.

Based on Woodbury-Sherman-Morrison formula, a general and efficient method for torsional damper tuning is presented. This method is based on exact calculation of the resulting Frequency Response Functions (FRF's) of the system with the damper by using the original (old) FRF's of the original (baseline) system and the damper's parameters (the mass polar moment of inertia, stiffness and damping coefficient). The only requirement for this method is to have the baseline FRF's at the active points of the structure where the damper is to be attached and those point where the resulting FRF's are of interest. The baseline FRF's can be obtained by either analytical or experimental methods. Once this requirement is met, all possible scenarios of the dampers for their potential and feasibility can be efficiently evaluated before being put into service without the need for costly hardware modification and test cycles on actual structure.

A process for simultaneously optimizing the mechanical performance and minimizing the weight of an automotive body-in-white will be developed herein. The process begins with appropriate load path definition though calculation of an optimized topology. Load paths are then converted to sheet metal, and initial critical cross sections are sized and shaped based on packaging, engineering judgment, and stress and stiffness approximations. As a general direction of design, section requirements are based on an overall vehicle “design for stiffness first” philosophy. Design for impact and durability requirements, which generally call for strength rather than stiffness, are then addressed by judicious application of the most recently developed automotive grade advanced high strength steels. Sheet metal gages, including tailored blanks design, are selected via experience and topometry optimization studies.