UCLA researchers send an experiment into orbit onboard Space Shuttle Discovery to investigate possible engine-cooling technology
On its last mission on Thursday, Space Shuttle Discovery flew the first UCLA-led research project into space.
The experiment, which will be carried out remotely on the International Space Station, may be the first step towards long, manned space journeys.
The necessities for an extended manned journey in space include technologies such as climate control and the ability to recycle water, said Gopinath Warrier, a research engineer with UCLA’s mechanical and aeronautical engineering department.
Because these things require a lot of power, Warrier said that an in-space power plant is a necessary advancement. But before that can be designed, scientists must figure out how to keep such a power plant cool.
And that is where the UCLA-led experiment comes in.
The experiment will investigate the effects of low-gravity on a process called nucleate boiling, said Vijay Dhir, the dean of the UCLA Henry Samueli School of Engineering and Applied Science.
Nucleate boiling is a process in which an object’s already hot surface is cooled down by bubbles that form on that surface when the liquid covering the object begins to boil.
When the bubbles leave the hot surface, they transfer heat away from the object, keeping it from becoming too hot.
“Nucleate boiling is the boiling process you normally observe when you cook food at home,” Warrier said. “When the water begins to boil, the bubbles coming from the bottom of the pot are nucleate boiling.”
After 12 years of research, the team is expecting to discover the way these vapor bubbles grow and interact in space, Dhir said. With this knowledge, he said that NASA could begin to study ways to use this method of cooling in space.
After doing experiments in normal gravity early in their research, the team tested the boiling system on the “Vomit Comet,” a plane that achieves low gravity by making high-atmosphere parabolic flights. But the ultimate goal has always been to get the project onto the space station, where the gravitational pull is one millionth of that on Earth, Warrier said.
While simulations have led the researchers to believe that these bubbles will grow much slower and larger in low-gravity conditions than they do on Earth, Dhir said that concrete evidence gained from running these experiments in space will give NASA more confidence to pursue this type of research.
Although he was not able to watch the launch in person, Dhir said that he was happy to see his team’s research get blasted into space on television.
“We have been working for several years now, and finally we have a chance to really see results,” he said.
Warrier said that there is still much work to be done before NASA begins to implement a cooling system that uses the nucleate boiling method.
The current experiment only tests nucleate boiling in a pool of liquid. The next step would be to look at a situation in which there is fluid flowing in a pipe and how this would affect the process, Warrier said.
“This is just a small stepping stone,” he said.
NASA has been taking projects like this one from universities into space since the early shuttle days, said Kelly Humphries, NASA spokesman at Johnson Space Center in Houston. At any given time, the International Space Station has 150 or more experiments going on, ranging from the physical to biological sciences and coming from researchers around the world.
“(NASA) funds hundreds of projects, but not all of them go up,” Warrier said. “(Our project) is one of the priority items for them.”
Looking at the cooling capabilities of this method in zero gravity is important to NASA because they are able to use the findings to develop systems for future spacecraft, Humphries said.
The project is currently at the International Space Station waiting to be installed by one of the station’s astronauts.
“I’ve spent a long time on it,” Warrier said. “It will be interesting to see what results we get and how they compare with our predictions.”