Updating of optimum designing method of flat composite panels

摘要

The flat panels consisting of package of N monolayers of various materials is considered. Panels are in flat stress-strain state under loading of P various forces. For composite panel critical loading the value of load is accepted, at which there will be fracture of the weakest layer. At the level-by-level analysis of fracture the strain criterion of Tsai-Wu is used. It is required for specific loads to find such values of thicknesses of monolayers /spl delta/; (i = 1, N), that the minimum of panel weight was provided at performance of restrictions on panel strength. Minimization of panel weight is made consistently. Let's choose any way a layer with number j. Then we shall record ratio of thickness of other layers of material. We minimize the panel weight, varying thickness of j-th layer with method of gold section. Performance of restrictions is provided with bisection method. Touching j from 1 up to N, we receive weight of an element on the given iteration. Then we compare weight with results of the previous iteration. If difference is more than given size, management is transferred by the beginning of iteration. The considered algorithm is realized by the program. As examples optimization of the flat composite panels made of materials AS4/3502 and HMS/3002M at action of loadings spectrum are considered. Comparison with the gradient method decision of these problems is given. Calculations have shown high speed of algorithm. Convergence is provided for two iterations. There is no necessity to calculate derivative criterion function. The opportunity of free choice of any suitable fracture criterion allows recommend the given algorithm to practical application by optimization of multilayered composite panels.