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Current U.S. Army ground vehicles predominately use commercial off-the-shelf or modified commercial diesel engines as the prime mover. Unique military engines are typically utilized when commercial products do not meet the mobility requirements of the particular ground vehicle in question. In either case, such engines traditionally have been calibrated using North American diesel fuel (DF-2) and Jet Propellant 8 (JP-8) compatibility wasn't given much consideration since any associated power loss due to the lower volumetric energy density was not an issue for most applications at then targeted climatic conditions. Furthermore, since the genesis of the ‘one fuel forward policy’ of using JP-8 as the single battlefield fuel there has been limited experience to truly assess fuel effects on diesel engine combustion systems until this decade.

Rose-Hulman Institute of Technology is designing a power-split hybrid-electric vehicle that uses three power sources: a 70 kW Diesel engine that uses B-20 Diesel fuel and two 60 kW induction electric machines. All three power sources are connected through a planetary gear set (PGS). The electric machines move the vehicle in forward or reverse, act as motors or generators, and one of the motors is required to control the speed of the engine. When the three power sources are combined with a battery that must be maintained within specific operating limits, the system becomes a challenging control problem. This paper discusses the simulation methods used to design and verify the operation of the supervisory controller that controls all aspects of vehicle operation.

The work reported here was initiated in the attempt to develop a bio-based two-cycle SI engine lubricant as an alternative to commercially available mineral based synthetics. In the first phase of the project, it was discovered that straight soy based biodiesel at any volume ratio with gasoline had insufficient lubricity to prevent engine seizure. Mixtures of synthetic with biodiesel proved to have adequate lubricity. A two-cycle lubricant was then synthesized via a trans-esterification of canola oil with hydrogen peroxide and vinegar forming canola oil based biodiesel (COBB). COBB proved to have superior lubricity to synthetic lubricant. The superior lubricity of COBB is hypothesized to be due to a saturated solution of non-reacted canola oil in the biodiesel. This hypothesis was tested using mixtures of canola oil in a solution of phenyl acetate as a two-cycle SI engine lubricant.

Rose-Hulman Institute of Technology is one of 17 universities competing in Challenge X - Crossover to Sustainable Mobility, an international competition where teams are challenged to design, build, and test a hybrid vehicle architecture utilizing alternative fuels to reduce the energy consumption and emissions production of a 2005 Chevrolet Equinox while maintaining stock performance, utility and safety. During the first year of competition, our team has capitalized on numerous new technologies in both modeling software and physical components. PSAT was employed for preliminary architecture screening and component sizing while The Mathworks Simulink, SimDriveline, and Stateflow provided the environment for modeling our selected architecture and powertrain components. Our modeling progressed to real-time verification via multiple NI PXI chassis and a local CAN network.

One of the deliverables for the GM/DOE sponsored EcoCAR2 competition involved the design and validation of an energy storage system (ESS) that could withstand 20g of acceleration in the longitudinal direction, 20g of acceleration in the lateral direction, and 8g of acceleration in the vertical direction with a minimum safety factor of 2, in the event of a crash. Rose-Hulman Institute of Technology (RHIT) elected to base their energy storage system off of A123 battery modules (7×15s2p) and components. The design included a thermal analysis for various drive cycles and a mechanical analysis of the enclosure built to support and protect the battery modules. The thermal analysis investigated passive cooling versus active cooling and, after identifying active cooling as the best strategy, an appropriately sized cooling loop was developed. The mechanical analysis involved the use of Siemens NX7.5 to develop CAD models for the ESS enclosure components.

Rose-Hulman Institute of Technology is one of 17 universities competing in Challenge X - Crossover to Sustainable Mobility, an international competition where teams are challenged to design, build, and test a hybrid vehicle architecture utilizing alternative fuels to reduce the energy consumption and emissions production of a 2005 Chevrolet Equinox. Our first year of competition has focused on vehicle simulation in which The MathWorks SimDriveline and Stateflow toolboxes have been used almost exclusively. A model of our vehicle's split train architecture was developed in SimDriveline and Stateflow was used to develop the control strategy. This approach was extraordinarily useful as we could readily identify hazards such as high torque stresses, battery over or under voltage spikes, battery over current spikes, wheel skidding, and rpm limits. We have been continuously improving our model and control strategy to uncover new hazards and verify components specifications and limits.