A finite element model development as a part of process of energy absorption material selection

The Warsaw Institute of Aviation major role in the RASTAS Spear project was to design an energy absorption system for the space probe lander. As the system was meant to be unmanned, the main requirement was to use no active solutions like parachute or rocket propulsion (less complexity in application and thus more reliability). A group of various materials was chosen to be tested. Tests campaign was divided into three stages: static compression tests, low speed dynamic tests and high speed dynamic tests. The high-speed dynamic tests were divided into two substages. In the first one simple cube specimens were tested to obtain data necessary for second substage in which full-scale object was tested. Having valuable data from experiments, numerical simulations in LS-DYNA software were carried out and then the results were compared. Based on experimental data several iterations during finite element model developing process were made. That process allowed setting up properly simulation by changing and adjusting properties such: material models, contact types, element formulation and other important constants. The finite element simulation results showed a good correlation with experimental data. The knowledge gained from numerical model optimization in connection with experimental data allowed for creating faster and more accurate energy absorbing material selection methodology. This methodology was successfully used in subsequent projects in which Institute of Aviation took part and also can be used in other future applications.