Victor Maldonado, associate professor, and Zeeshan Ahmad, assistant professor, in the Department of Mechanical and Aerospace Engineering in the Edward E. Whitacre Jr. College of Engineering (WCOE), have each received $50,000 from NASA for two independent projects.
Building-Aware Flights for Safe Urban Air Mobility
Maldonado will study the impact of wind turbulence on electric vertical takeoff and landing (eVTOL) vehicles in densely populated urban environments.
It is expected that eVTOL travel in urban areas, the air travel equivalent of ordering an UBER, is not far on the horizon of possibility but some limitations remain a hurdle.
Safety certification for eVTOL travel is currently only completed for ground level point-to-point travel across an open field. Before eVTOL travel in densely populated urban areas becomes a reality, this mode of transportation must meet safety certifications.
“Flight safety is critical to the broader use of eVTOL aircraft in civilian applications. Dr. Maldonado’s research will help make these technologies safer and more reliable,” said Charng-Song Kong, department chair for the WCOE Department of Mechanical and Aerospace Engineering.
The most significant challenge is to ensure low altitude flight safety from vertiports (for example, a helipad on top of a building) in complex urban atmospheric wind conditions, which involve a lot of turbulence and unpredictability.
There is limited information available on urban environment wind conditions on Urban Air Mobility (UAM) vehicles.
To address this challenge, Maldonado will build a scaled model of the eVTOL and building structures to test at the NSF Wall-of-Wind Experimental Facility (WOW-EF) at Florida International University, which can reproduce realistic urban atmospheric flow physics at scales relevant to Urban Air Mobility (UAM) operations. This facility produces a large 14 ft. high by 20 ft. wide turbulent flow field.
“This project is the first to combine large-scale physical modeling, advanced flow diagnostics, and UAM testing to obtain the data necessary to examine how real UAM aircraft behave in these conditions,” explained Maldonado. “We expect that our research will be used to provide guidelines for placement of vertiports and operations of eVTOL in urban environments in the future.”
Low Temperature Sodium Batteries
Ahmad’s research aims to develop a sodium ion battery for lunar space missions by designing an electrolyte that facilitates rapid sodium ion transport at low temperatures, addressing one of the major challenges of battery performance in space.
Lithium-ion batteries are valued because they give the highest energy density, but they are susceptible to performance degradation at very low temperatures in space, which cause the current to move very slowly. Currently, space flight missions use a thermal management system to maintain the battery’s temperature at a level that allows the current to flow at acceptable levels. This solution adds weight to the mission as well as the need for an additional power supply.
“Lunar missions present unique challenges and require batteries designed for very different conditions. Dr. Ahmad’s sodium-ion approach could offer a promising option for powering future missions to the moon,” Kong said.
Ahmad proposes to use sodium ion batteries instead of lithium because sodium batteries do not see as significant a loss in transport at low temperatures.
In addition, Ahmad plans to speed up the ion movement by changing the composition of the sodium ion battery’s electrolyte, using machine learning-based simulation to design a co-solvent.
“The goal is to develop a battery that allows the sodium ion to move more efficiently within the electrolyte and at the interfaces at faster rates so that the heating system is not necessary,” explained Ahmad.
Both projects are expected to be completed in six months and are intended to lead to the next phase of research to advance each specific goal.