LATTICE STRUCTURE ANALYSIS AS ENERGY ABSORBTION AND ITS APLICATION TO AIRCRAFT SUB-CARGO

• Main Author: Iqbal Hanif Nasrullah, Alvian
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/33520
• Institution: Institut Teknologi Bandung

The high air traffic makes incident opportunities increasing. Most cases of aircraft accidents cause the underside of the airframe (sub-cargo) due to vertical dynamic loads. To improve the airplane's crashworthiness and reduce the injury of the passanger, an aircraft crashworthiness study was conducted. One of the ways increasing energy management of aircraft absorbtion against impact is by optimizing the energy absorbent structure. Improving the energy absorbent structure can be done by optimizing the geometry and material structure The lattice structure is one of the best lightweight application types in energy absorbent applications. This thesis focuses on the characterization of dynamic loads on lattice structures and their application to aircraft sub-cargo structures. Eleven types of lattice are examined to look for the highest specific energy absorbtion, i.e. kagome, tetrahedron, pyramid, cube, truncated-pyramid, octahedron, rhombicuboctahedron, rhombic-dodecahedron, open-cell, octet, and octet topology optimization structures (twisted). The analysis is performed on one cell unit of the lattice structure. With the existence of additive manufacturing technology, lattice structures can be easily used using selective laser sintering (SLS) technique. The material that used in numerical simulation is aluminum alloy AlSi-12 by SLS manufacturing. The best lattice type is chosen for later used in the numerical simulation of the aircraft sub-cargo structure. The model of the aircraft used is rear fuselage structure of AIRBUS A320. The drop-weight test is performed with an initial velocity of 9 m/s. The results of energy absorbtion on lattice sub- cargo structure will be compared with the half-tube sub-cargo structure which has been widely used in aviation industry. Stuructural taper effect is used to make higher absorption energy. From the simulation results, lattice type with the highest SEA value is twisted type with relative density 0,2 in the amount of 127,21 kJ/kg. The form of dominance that occurs in the structure determines the amount of energy that can be absorbed. These results indicate the suitability of the lattice structure as an energy absorber on an aircraft in the future.