An airflow simulation program may help make space travel safer and less expensive.
The University of Minnesota is participating in a program based in Australia that could revolutionize space travel by making it safer, more economical and environmentally responsible. A unique software program developed at the University will be used by a consortium with a goal to develop a scramjet — a spacecraft that takes the oxygen necessary for takeoff out of the atmosphere instead of carrying it in a tank, which enables it to be smaller, lighter and faster. The program, led by the University of Queensland in Australia, was recently awarded $14 million for the first phase of a consortium that has a 20-year road map to produce a scramjet accessible for space travel. The first phase will address scramjet performance by analyzing data from ground-based experiments, according to the funding proposal authored by the consortium members. Graham Candler, a University of Minnesota professor in the department of aerospace engineering and mechanics, will lead the research group that will provide the data analysis program. The program uses computational fluid dynamics code, which simulates the flow of gases and liquids over vehicles that travel at hypersonic speeds like the scramjet. “The code that they are going to be using is unique,” Candler said. “There are other methods out there that they could use, but they are just not as good.” Candler’s code uses a number of distinct equations that describe the flow of air and liquid over an object at extremely high speeds in a program that can run on various computers. Russell Boyce, professor at the University of Queensland and director of the project, said the code, which is titled US3D, will provide validation of the project outcomes. “US3D is one of the world’s leading flow simulation tools for hypersonics,” Boyce said. Erik Tylczak, a graduate research assistant in the department of aerospace and engineering, said the code works well with the technique the scramjet uses to introduce fuel to the atmospheric oxygen passing through the body. “Our techniques are well suited towards an effective and computationally low-cost evaluation of fuel and air mixing,” Tylczak said. Candler said he is confident in the abilities of Boyce and the Australian institutions. “In an academic world, they are a world leader in what they are doing with combining ground, wind tunnel and flight testing,” he said. Although their expertise in the field is well known, Boyce said the consortium will depend on each member from around the world to achieve their goal. “Australia would not be able to do it all ourselves,” Boyce said. “But bring us all together and you can get the pieces in place to actually achieve something.” Participating with the University of Minnesota are the universities of Queensland, Adelaide, New South Wales and Southern Queensland. Candler said the University’s involvement will not give them access to any funds but will provide access to something he feels is more important than any monetary compensation. “We will not have access to any money flow here,” he said. “But we will have access to the unique data and to the expertise that they have.” Candler said their involvement builds credibility for the University’s simulation tools, and this credibility could be recognized by institutions like NASA and the U.S. Air Force in the future. Tylczak said the involvement could extend the usage of the code into fields where it has not yet been used. “It is an exciting opportunity to spread the knowledge of our competence beyond the more limited community with whom we usually work,” Tylczak said. Candler said his involvement with scramjets dates back to five years ago when he first became involved in a project run by the Defense Advanced Research Projects Agency. In July 2007, Candler helped design a flight for a DARPA program, which launched a scramjet that traveled at Mach 10, or about 7,600 mph — considerably less than the Mach 14 speeds required to leave the Earth’s atmosphere. Candler said reaching speeds of this magnitude will take considerable time, and the first phase of the 20-year road map will provide a base that future research can build on. “This is really the basement of the building before you actually produce something that is going to fly,” he said. The technology necessary for a scramjet to reach space has not yet been developed and may be impossible, but Candler said these questions cannot be answered until they are encountered. “You don’t know what is needed until you go down the path,” he said. If all of the questions are successfully answered and a scramjet is developed 20 years from now, Candler said space travel will be much safer with an abort scenario being possible. “It will be safer because you are flying something with aerodynamic performance,” he said. “If something goes wrong, you can fly back and survive a malfunction.” The scramjet is less expensive, according to Candler, who said this could result in endless possibilities for making space more useful. “If you were to launch things at one-tenth of the cost, there may be things that would happen in space that we don’t even know about,” he said.