On December 9, at the Marshall Space Center in Hunstville, Alabama, NASA engineers conducted a unique experiment that sought to destroy a giant "can" with a force. up to 1 million pounds (more than 450 tons). The demolition experiment is part of a fuel tank design project for Space Launch System (SLS) - the system will be used to launch Orion spacecraft onto orbit and carry out deep space missions.
Liquid fuel boosters were originally equipped with large containers in the body. However, in the 1950s, engineers realized that fuel tanks were an unnecessary waste of weight and rocket flexibility. Their answer was to turn the entire body of the rocket into a fuel tank. By the 1960s, the idea of a body-cum-fuel-rocket design continued to be promoted during the space race (Space Race) with the result that giant cylindrical metal chambers filled with fuel, accumulated in accordance with the missile structure.
This approach solves many problems but also generates many other problems. The missile body not only covers internal equipment but also suffers from pressure, impact control, etc. Therefore, the body needs to ensure stability to maintain the missile structure.
NASA's test, Shell Buckling Knockdown Factor Project, was performed at the Marshall Space Center's dynamic and structural engineering laboratory. This is also the test site of the Saturn V rocket, Space Shuttle shuttle and components of the ISS international space station. The tested fuel tank is an unused component of the shuttle. The 8.3m-diameter barrel, made of aluminum-lithium alloy and NASA said its structure is similar to the SLS fuel tanks.
The purpose of the test is to control the fuel tank during the SLS launch. The pressure vessel is used to simulate flight conditions and to observe tolerance to internal pressure, compressive forces and bending forces that can twist the structure.
Mark Hilburger - research engineer at the mechanical and structural ideas division at NASA's Langley Research Center in Hampton, Virginia, said: "When the barrel was bent, we heard bang bang, near like thunder and can see big bumps on the subject. "
The bending rate is measured by a technique called Digital Image Correlation . The barrel is painted 70,000 points of irregular black and white fillings. Around the barrel are 22 high-speed cameras that constantly monitor paint spots and record every curve, tear or stretch by measuring every movement of paint spots on a large area of the barrel.
The goal of the test is to find a way to reduce the weight of SLS by 20%. This will allow the thrust system to be heavier and the mission can go further into deep space.
"In addition to providing data for the Space Launch System design team, the tests will be a preparation for larger scale tests. Implementation of structural tests on hardware with size SLS's hardware equivalent will bring great benefits to the development of future names , " said Matt Cash, head of the engineering team at Shell Buckling project at Marshall.