"Gas stations" in zero gravity: A Purdue experiment lays the groundwork for cryogenic fuel storage in space.
Introduction
Scientists are beginning to understand how cryogenic liquids behave in zero gravity and how this affects the future operation of propellant depots in space. To journey and return from other planets, future spacecraft may have to refuel in space - an experiment at Purdue University has shed light on how this might happen.
The function of gas stations in space and a challenge
Almost all spacecraft are currently fuelled by cryogenic liquid fuel.
On Earth, When we establish propellant depots in space and begin refilling spacecraft in orbit, we must understand how those liquids will react in a zero-gravity environment. Cryogenic liquids differ from other fluids, such as water and other typical coolants, in their behavior. The only place to do large-scale cryogen research in zero gravity is during a parabolic flight. On Earth, we know how these super-cooled liquids behave.
The solution - An incredible collaboration
Issam Mudawar's Ruth and Hollander Family Professor of Mechanical Engineering - Boiling and Two-Phase Flow Laboratory has a long history of establishing foundational heat transfer science. His work with NASA's Glenn Research Center resulted in the largest phase change experiment ever launched into space, currently being carried out on the International Space Station.
Mudawar was awarded to develop and build a cryogenic experiment to fly on a Zero Gravity Corporation (ZERO-G) parabolic flight, in which an airplane mimics periods of 15-17 seconds of microgravity by flying up-and-down parabolas.
The Result and Future
According to Mudawar, the test rig and operation ran successfully. "These technologies are critical not only for space systems in low Earth orbit but also for fueling future expeditions to the Moon and Mars."