Characterization of the Behavior of a Hybrid Electric Vehicle Powertrain Fueled by an Ammonia-Gasoline-Ethanol Tertiary Fuel Blend 2020-01-5105

With the depletion of petroleum resources around the world, the need to have fuel-efficient mobility solutions and sustainable alternative fuels for automobiles has become prominent. Hybrid Electric Vehicles (HEV) and Battery Electric Vehicles have recently gained attention in terms of fuel-efficient mobility solutions. Recent research work by the authors of these articles and many other research groups have demonstrated the suitability of ammonia as a sustainable alternative power for automobiles [1, 2, 3, 4, 5, 6, 7, 9, 18]. Ammonia has been used for a long period of time mainly as an agricultural chemical and as a sustainable and carbon-free fuel and has substantial potential as a liquid fuel for mobile applications [1, 2, 3, 4, 5, 6, 7]. Ammonia-rich fuels can be used to run HEVs equipped with an Internal Combustion Engine (ICE) as the primary power source and a battery as the secondary energy source. When compared to conventional automobiles, HEVs have a complex powertrain with ICEs, high-voltage batteries, and electric motor-generators. Sophisticated control systems are used to control these components to satisfying the user power demands while achieving the best possible fuel economy. This sophisticated control system could be optimized to the fuel being used and many other driving conditions. The feasibility of the ammonia-rich fuel to power the existing ICEs of an HEV and the final fuel efficiency with an optimized control system for these fuel blends are studied in this research using an engine dynamometer setup to characterize the performance of the fuels and high fidelity computer-aided engineering (CAE) simulation model of a series HEV to optimize the control system and predict the fuel economy. CAE models eliminate the need of having expensive hardware prototypes required for preliminary stage feasibility studies of alternative energy applications. This paper also demonstrates the successful usage of CAE models in lieu of expensive hardware prototypes for such studies. Results from the engine dynamometer tests show that ammonia-rich fuels are capable of producing equal power and torque compared to baseline gasoline-only fuels. At higher engine speed ammonia-rich fuels are capable of producing about 5-8% more power and torque. CAE simulations show an ammonia-rich fuel has improved the fuel economy of the HEV by 2-22.75% (with and without control system optimization) over the baseline gasoline fuel when tested with Environmental Protection Agency (EPA) regulatory drive cycles. Finally, it is proven that ammonia, which is an already widely used chemical, could successfully be used to replace a part of the petroleum (gasoline) fuel requirements of existing ICEs and, if used with an optimized control system in an HEV ammonia-rich fuels, yields a higher fuel economy.