模拟正常动脉壁残余应变和应力的数值研究

Numerical Study on Residual Strains and Stresses Simulation in Healthy Arterial Wall

目的探讨残余应变对动脉壁周向应力-应变分布的影响。方法构造残余应变数值施加方法,对在不同生理血压下的动脉壁应力-应变进行数值模拟,并且模拟了残余应变使动脉圆环张开的情形。结果动脉壁的周向应力水平明显降低;周向应变沿壁厚的分布趋于均匀;动脉圆环的张开角α大致为7°。结论残余应变降低了载荷状态下的应力水平;残余应变直接改变了载荷状态下动脉壁沿径向的周向应变分布;残余应变的存在会使无载荷状态的动脉圆环发生张开;血管壁优化状态体现了均匀应变优化标准。

Objective To study the effect of residual strains on the distribution of circumferential stresses and strains of normal arterial wall. Methods The numerical application method of residual strain was constructed. The stresses and the strains of arterial wall under different physiological blood pressures were calculated. The opening angle of arterial wall was simulated. Results The residual strains resulted in the circumferential stress level falling markedly and the circumferential strain distribution along wall thickness going even; The opening angle of artery circle was estimated 7 degrees. ConcIusions Residual strains reduced stress level at the loaded state; Residual strains changed circumferential strain distribution along wall thickness at the loaded state directly; Residual strains made blood vessel circle open at the non-loaded state; The optimization state of blood vessel wall embodied uniform strain optimization criterion.