Mechanical Study On Arterial Wall With Three-Dimensional Residual Strain Factor

The effect of residual strain on stress and strain distribution of blood vessels has been investigated widely. The important effect of residual stress/strain on circumferential stress-strain of blood vessel wall along wall thickness has been proved by experiments and theories respectively. Though there are already many studies on residual strain, they are almost based on experiment and mathematical illation and numerical methods aren't applied on them. So it's difficult that they are applied on the analysis of hemodynamics of in-vivo blood vessel. How residual strain of arteries is applied in numerical analysis has been a difficult issue for many years. Especially, the application of residual strain of arteries with complicated geometrical factor is still a very difficult issue at present. In the paper, the numerical methods of arteries with residual strain factor were discussed in the condition of straight blood vessel. The finite element method was applied and the method of residual strain application in numerical analysis was proposed. Then the residual strain was added to finite element model of blood vessel segment as an initial condition. The stress and the strain of blood vessel wall under different physiological blood pressure were calculated. The stress-strain distribution of blood vessel wall was calculated and the effect of residual strain was studied and the opening angle of blood vessel wall was simulated. The numerical results shew that the residual strains make the circumferential stress level falling markedly; and they make the circumferential strain distribution along wall thickness going even; the opening angle of blood vessel circle is 7 degrees. We drew the following conclusion: residual strain reduces stress level under loaded state; residual strain changes circumferential strain distribution along radial direction under loaded state directly; residual strain makes blood vessel circle open under non-loaded state; the method of residual strain application in the paper is effective.In the paper, the possibility of mechanical factor optimization of arteries was obtained by analyzing the effect of residual strain of arteries. That was to say, uniform strain optimization criterion. The signification was that the determinant should be strain and not be stress in life optimization, which affected theoretical study and...