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This paper presents the work performed by the Wayne State University (WSU) EcoCAR 3 student design competition team in its preparation for the hybrid electric vehicle architecture selection process. This process is recognized as one of the most pivotal steps in the EcoCAR 3 competition. With a key lesson learned from participation in EcoCAR 2 on “truly learning how to learn,” the team held additional training sessions on architecture selection tools and exercises with the goal of improving both fundamental and procedural skills. The work conducted represents a combination of the architecture feasibility study and final selection process in terms of content and procedure, respectively. At the end of this study the team was able to identify four potentially viable hybrid powertrain architectures, and thoroughly analyze the performance and packaging feasibility of various component options.

There is a need for high efficiency radiators in liquid cooled military vehicles. It is obvious that the new system should be better than the current Al radiators in terms of thermal performance, military robustness, size, weight and easiness of mass production. For the last ten to fifteen years, a search for new materials has been ongoing. One of the best current candidates is a pitch-based carbon foam that exhibits a superior thermal performance, but with inferior mechanical performance. While developing carbon foam systems, with the intent of overcoming its seriously low mechanical strength, it was also discovered that another serious concern emerged, namely the difficulty in joining, bonding and sealing the carbon foam to the same, or dissimilar material, such as metal or ceramic. This paper presents results of our first stage effort in strengthening carbon foam under an SBIR program funded by the National Automotive Center (NAC) at TACOM, Warren, MI.

Cerebral blood vessels are an integral part of the brain and may play a role in the response of the brain to impact. The purpose of this study was to quantify the effects of surrogate vessels on the deformation patterns of a physical model of the brain under various impact conditions. Silicone gel and tubing were used as surrogates for brain tissue and blood vessels, respectively. Two aluminum cylinders representing a coronal section of the brain were constructed. One cylinder was filled with silicone gel only, and the other was filled with silicone gel and silicone tubing arranged in the radial direction in the peripheral region. An array of markers was embedded in the gel in both cylinders to facilitate strain calculation via high-speed video analysis. Both cylinders were simultaneously subjected to a combination of linear and angular acceleration using a two-segment pendulum.

A liquid fuelled, fuel cell auxiliary power unit (APU) can provide efficient, quiet and low pollution power for a variety of applications including commercial and military vehicles. Truck idling regulation, customer comfort or military “stealth” operation by using electrical power, require a device disconnected from the main diesel engine. The power can be utilized for air conditioning as well as other auxiliary systems found on board commercial trucks for driver comfort. In a military vehicle, this regulated power could be supplied to telecommunication and other computer equipment required for military operations. A system designed to be an add-on or retrofit solution using alternative fuel can have the potential to meet these requirements on the hundreds of thousands of existing vehicles currently in service or as optional equipment on a newly procured vehicle.

In military vehicles reliability can sometimes be a more important issue than cost. With that in perspective, this paper discusses the load availability and reliability issues in automotive multiplexed wiring harness systems, which are potentially useful in the military, and compares the same with a regular non-multiplexed system. For that purpose, a figure of merit or metric is introduced, and the load availability is described in terms of this metric, which depends on the architecture chosen.

The effects of the start/stop (S/S) transients on the Hybrid Electric Vehicle (HEV) operation and emissions are explored in this study. The frequency with which the engine starts and stops during an urban driving cycle is estimated by using the NREL's Advanced Vehicle Simulator software (ADVISOR). Furthermore, several tests were conducted on single-cylinder and multi-cylinder direct injection diesel engines in order to measure the cycle-resolved mole fractions of the hydrocarbons and nitric oxide exhaust emissions under frequent start/stop mode of operation. The frictional losses in engine in its entirety as well as in its components are also determined. In addition, the dynamic behavior of different high pressure fuel injection systems are investigated under the start and stop mode of operation.

Dynamic data, forces, moments and displacements are widely used parameters in a simulation environment for design and testing. These results may be obtained from field tests, laboratory measurements, and numerical simulations. The correctness of the simulation results depends strongly on the models and numerical solution techniques. This paper presents a preliminary examination of the differences between results obtained from the computer code DADS (Dynamic Analysis and Design System) [1] and the field data for the response of a military tank. The differences are analyzed by standard statistical methods in the frequency domain. The statistical tests show that DADS results differ from the measured field data and that the errors are not white noise. Moreover, the principal frequencies of the differences are identified.