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For the past approximately 20 years, the Serial Peripheral Interface (SPI) has been the established standard for serial communication between a host or central microprocessor and peripheral devices. This standard has been used extensively in control modules covering the entire spectrum of automotive applications, as well as non-automotive applications. As the complexity of engine control modules grows, with the number of vehicle actuators being controlled and monitored increasing, the number of loads the central microprocessor has to manage is growing accordingly. These loads are typically controlled using discrete and pulse-width modulated (PWM) outputs from the microcontroller when real-time operation is essential or via SPI when real-time response is not critical. The increase of already high pin-count on microcontrollers, the associated routing effort and demand for connected power stages is a concern of cost and reliability for future ECU designs.

This paper presents a mechanical energy control volume analysis for incompressible flow around road vehicles using results from Detached Eddy Simulation Computational Fluid Dynamics calculations. The control volume approach equates the rate of work done by surface forces of the vehicle to (i) the rate of work and kinetic energy flux at the control volume boundaries (particularly in the vehicle wake) and (ii) the rate of energy loss in the domain. At the downstream control volume boundary, the wake terms can be divided into lift-induced and profile drag terms. The rate of energy loss in the domain can be used as a volumetric analog for drag (drag counts/m3, when normalized). This allows for a quantitative break down of the contributions of different flow features/regions to the overall drag force.

This paper presents an extensive set of permeation data on automotive fuel system materials. It adds significantly to the information provided by the same authors in SAE paper 983160 [1]. The permeation measurements refer to three different test fuels: fuel C, CE10 and CM15 at 40, 50 and 60°C. The materials examined include poly-ethylenes, nylons, polyketons, ethylene-vinyl alcohol copolymers, acetals, fluoropolymers and fluoroelastomers. These data are important in the design of automotive fuel system components capable of meeting LEVII or PZEV requirements. In particular, data of this kind are crucial in optimizing the permeation performance of multilayer structures for fuel system applications.

The process of assembling the bearing and crimp ring to the steering pinion shaft is intricate. The bearing is pressed into its position via the crimp ring, which is tipped inward and fully fitted into a groove on the pinion shaft. Only when the bearing is pressed to a low surface on the pinion shaft, the caulking force for the crimp ring is achieved. The final caulking distance for the crimp ring confirms the proper bearing position. Simulating this transient fitting process using CAE is a challenging topic. Key factors include controlling applied force, defining contact between bearing and pinion surface, and defining contact between crimp ring and bearing surface from full close to half open transition. The overall CAE process is validated through correlation with testing.

The deionized water/ethylene glycol coolant used in the Ford Focus Fuel Cell Vehicle (FCV) requires very low conductivity (< 5 μS/cm) to avoid current leakage and short circuiting, presenting a unique water chemistry issue. The coolant's initially low conductivity increases as: 1) ions are released from system materials through leaching, degradation and/or corrosion, and 2) organic acids are produced by ethylene glycol degradation. Estimating the leaching potential of these ions is necessary for design and operation of fuel cell vehicles. An on-board mixed-bed, ion exchange resin filter is used to maintain low conductivity by removing leached or produced ions. Various candidate materials were evaluated for leaching potential by exposing them to coolant at the design operating temperature for several months and periodically analyzing the coolant for ions.

Mechanical shock tests for lithium metal and lithium-ion batteries often require that each cell or battery pack be subjected to multiple shocks in the positive and negative directions, of three mutually perpendicular orientations. This paper focuses on the no-disassembly requirement of those testing conditions and on the CAE methodology specifically developed to perform this assessment. Ford Motor Company developed a CAE analysis method to simulate this type of test and assess the possibility of cell dislodging. This CAE method helps identify and diagnose potential failure modes, thus guiding the Design Team in developing a strategy to meet the required performance under shock test loads. The final CAE-driven design focuses on the structural requirement and optimization, and leads to cost savings without compromising cell or pack mechanical performance.