Data collected from these experiments will be used for future rockets

Dec 17, 2013 21:01 GMT  ·  By

Scientists at the NASA Marshall Space Flight Center (MSFC), in Huntsville, Alabama, had their hands full last week. Starting December 9, the Shell Buckling Knockdown Factor Project began conducting a series of crushing tests on large fuel tanks, meant to assess how these components deal with pressure. 

The end goal here is to determine how various rocket components react to the extremely stressful conditions met shortly after launch, during the first leg of delivery systems' journeys to Earth's orbit.

In this particular series of experiments, a fuel tank was subjected to almost a million pounds (453.592 kilograms) of force, which squashed it just like you would a beverage can under the soles of your shoe.

The entire procedure was observed closely with a series of 20 video cameras arrayed around the empty fuel tank, which observed a polka dot-style patterns imprinted on the surface of the test article.

The cameras feeds were centralized in a software that analyzed minute displacements in the positions of the dots, so MSFC engineers were able to track how the tank gave way under the extreme pressure.

Though empty, the fuel tank was pressurized to imitate conditions such as those that will be present in the tanks aboard the Space Launch System, NASA's next big rocket. Its maiden flight will take place in 2018, and the agency has great plans for it, including taking astronauts to an asteroid and Mars.

“These full-scale tests along with our computer models and subscale tests will help NASA and industry design lighter, more affordable launch vehicles. We were looking at real-time data from 20 cameras and more than 800 sensors during the final test,” says senior research engineer Mark Hilburger.

The expert holds an appointment with the Structural Mechanics and Concepts Branch at the NASA Langley Research Center, in Hampton, Virginia. He is also in charge of managing these tests for the NASA Engineering and Safety Center (NESC), which is providing funding for the SBKFP.

A total of 70,000 black and white polka dots were installed around the aluminum-lithium fuel tank. As buckles, ripples and strains began occurring on its surface, high-speed cameras monitored their spread and behavior in great detail.

“When it buckled it was quite dramatic. We heard the bang, almost like the sound of thunder and could see the large buckles in the test article,” Hillburger says, adding that these data will enable experts to create updated guidelines for building more efficient, lighter rockets that remain sturdy under stress.