METHOD FOR DETERMINING GEOMETRY OF STRUCTURE

摘要

PROBLEM TO BE SOLVED: To provide a method for determining the geometry of a structure capable of determining, with greater ease and higher accuracy than conventional methods, the geometry of a structure having a desired natural frequency. SOLUTION: For each of a plurality of finite elements, strain energy density U' and kinetic energy density T' are computed. Volume variation dV is computed on the assumption that for each of the plurality of finite elements, volume sensitivity dΩ/dV, a frequency difference dΩ, the natural frequencyΩ1rof an estimated structure, strain energy density U' and kinetic energy density T' are in a relationship of dΩ/dV=(U'-T')/2Ω1r. The volume variation dV is found and the shape and dimensions of each finite element of the estimated structure are changed to provide a new estimated structure. COPYRIGHT: (C)2007,JPO&INPIT