考虑流固耦合的大型渡槽横向动力分析

渡槽槽身是一种薄壁构件,在建立其动力分析模型时除应考虑渡槽槽身横向、竖向、纵向以及自由扭转变形外,还应考虑渡槽薄壁结构约束扭转变形以及槽内有水时水体对槽身的流-固动力相互作用.为此,依据符拉索夫及豪斯纳尔理论建立了考虑槽内水体与槽身动力相互作用的渡槽薄壁结构横向动力分析模型,由能量变分原理推导给出渡槽薄壁梁段单元刚度矩阵及质量矩阵表达式,通过数值算例验证了该模型的正确性;利用该模型对某大型渡槽进行了多种工况的频率计算,计算结果表明该大型渡槽在无水和设计水位时,其振动频率有所变化.该模型计算简单,是考虑渡槽槽内水体横向流-固动力相互作用的实用动力分析模型.

Transverse dynamic analysis of large scale aqueduct with fluid-structure coupling

The aqueduct is the thin wall-bar structure. In this dynamical analysis model, the transversal, vertical, longitudinal and freely torsion deformations, the constrained torsion deformation as well as fluid-structure coupling between aqueduct and water body are all taken into consideration. Based on the theory of Volasov and Housner, the transversal dynamical analysis model with fluid-structure coupling is established for thin wall-bar structure. The element stiffness and mass matrices of the aqueduct thin wall are derived by energy variation principle. The analytical formulations are deduced in the cases of no water and the design water level in aqueduct. Using this model, the frequencies in several cases are calculated and compared. The result shows that the frequencies are changed in one case with water and in the other case without water. The model is simple and practical for dynamic analysis of the fluid-structure coupling aqueduct.