Flexible object simulation systems are mainly based on geometrical , physical and hybrid techniques . since adopting physical technique can not only embody the appearance but also analyze the internal structure of flexible object and obtain satisfying results , so the algorithm proposed here depends on this technique . the bottle - neck in most flexible object simulation systems is that time steps must be small to avoid numerical instability and the huge computation cost 柔體的仿真方法主要以幾何技術(shù)、物理技術(shù)和混合技術(shù)為基礎(chǔ),由于物理技術(shù)不僅能反映柔體的外部特征,而且能對(duì)其內(nèi)部結(jié)構(gòu)進(jìn)行深入的分析,所以在本文進(jìn)一步研究的過程中,以該技術(shù)為主要的研究手段。
Based on tree data structure , the cartesian grids about 2 - d and 3 - d configurations are generated using the surface - cutting procedure . in the course of grid generation , a two - step ray - casting algorithm to excluded cells inside the body and a cell - merging technique to avoid numerical instability are fully developed . after creating these surrounding grids , the cell - cutting algorithm is designed to perform geometry - based refinement of grids , and greatly improve the applicability and quality of grid generation 采用物面切割,基于叉樹數(shù)據(jù)結(jié)構(gòu),發(fā)展了一種普遍適用于二維和三維外形的直角切割網(wǎng)格生成方法;構(gòu)造兩步射線求交算法,刪除外形內(nèi)的固體網(wǎng)格,以及小網(wǎng)格合并算法,確保網(wǎng)格質(zhì)量和流場(chǎng)計(jì)算的穩(wěn)定性;運(yùn)用對(duì)任意網(wǎng)格的切割細(xì)分算法,實(shí)現(xiàn)了針對(duì)幾何外形的自適應(yīng)網(wǎng)格加密,使得網(wǎng)格生成更具普適性和靈活性。