(6co) Design of Novel Hydrogen and Compressed Natural Gas Fueling Stations

Authors: 
Olmos, F., UCLA

During my PhD at UCLA under Prof. Manousiouthakis, the field of research I have been working on is hydrogen economy, specifically about the distribution of hydrogen fuel to the end user. One of the key challenges for the deployment of hydrogen fuel cell vehicles is the lack of fill-up practices that are time efficient and safe. Moreover, hydrogen fueling station operators do not employ an optimal mass flowrate policy that can satisfy the aforementioned constraints. A hydrogen vehicle user will like that the replenishment of fuel to his/her vehicle take the same time as a gasoline car. On the other hand, the type IV tanks, based on carbon fiber wrapping, have a maximum temperature limitation of 85 degree Celsius, so the fill-up process must ensure that this temperature is not surpassed. The research I have conducted has led to the development novel mathematical models and software that can simulate and optimize the fill-up process of gas fuel such as hydrogen, and even compressed natural gas (CNG). The models are based on a self-consistent thermodynamic model for real gases, transport phenomena principles, and conservations laws, which predict hydrogen’s temperature and pressure time evolutions inside the vehicle tank, the station storage tank, the piping connecting the tanks, and the dispenser isenthalpic valve. The model results have proven to match, within 2%, corresponding experimental data from an actual fill-up process. Furthermore, in order to minimize the fill-up time and to determine an optimum mass flowrate policy, I formulated the fill-up process as a minimum time optimal control problem, which through the used of a novel decomposition of the problem into a process simulation problem, that checks for feasibility of the fill-up independent of time, and a simple minimum time optimal control problem, the global minimum fill-up time can be obtained analytically along with an optimal control policy on the mass flowrate. The optimization studies results lead to a fill-up time strategy that can improve current fill-up practices.

In addition to my core research, I have also performed as the safety officer for Prof. Manousiouthakis experimental lab, having to go to intensive safety training and yearly inspections. Additionally, I have participated in the construction of the UCLA hydrogen fuel cell go-kart, and I have served as hydrogen system lead, safety inspector, and project leader. I am a very active member of UCLA Center for Excellence in Engineering and Diversity efforts to motivate students coming from minority populations to attend the UCLA engineering school. I have been participating in the Mathematics Engineering Science Achievement (MESA) program, laboratory tours, panels, talks, tutoring, and volunteering and organizing events since 2006. My research interests are alternative energy sources for vehicles, production of “green” hydrogen, design of hydrogen fueling stations, hydrogen safety, and hydrogen fuel cell vehicles integration.

Topics: