北京生物醫(yī)學工程

主動脈弓周向應力的非線性數(shù)值研究

Nonlinear Numerical Study on Circumferential Stress of Aortic Arch

作者：李坤李曉陽

單位：北京工業(yè)大學機電學院（北京100124）

分類號：

出版年·卷·期（頁碼）：2010·29·5（497-502）

摘要：

目的利用非線性數(shù)值計算模型研究人體主動脈弓的周向應力分布狀態(tài)，為臨床治療主動脈弓夾層提供生物力學依據(jù)。方法在有限元軟件ANSYS中建立主動脈弓的簡化模型，采用非線性M-R兩參數(shù)模型定義材料物理性質，計算得出非線性模型上6個特定截面上的周向應力數(shù)值，分析周向應力分布及變化趨勢，并與應用線彈性模型的計算結果作對比。結果與應用線彈性模型比較，利用非線性模型得到的不同截面的周向應力分布有很大差異；在彎管段同一截面的不同方向上的周向應力分布也不相同；非線性模型的應力變化趨勢和線彈性模型的基本相同，但應力水平低于線彈性模型。結論材料非線性會對主動脈弓的周向應力分布產生較大影響。

Objective To study the circumferential stress distributions of human’s aortic arch by a nonlinear numerical calculation model and provide the biomechanical basis for treating the disease of aortic dissection in clinic. Methods After building the simplified model of aortic arch using ANSYS, the circumferential stress values on six particular sections of nonlinear model were obtained, using a nonlinear two-parameter model which is one of M-R model to define physical properties of material, aiming at analyzing the characteristic of circumferential stress in nonlinear model and comparing with elastic model.Results The circumferential stress distributions of six sections in nonlinear model were great different from those of linear model. In the nonlinear model, the circumferential stresses among different directions were different at same section in the bend tube. However, along with the tube, the change tendency of stress distribution in nonlinear model was nearly same as that of linear elastic model, and the value level of stress was lower than the linear model’s.Conclusion The material nonlinearity strongly affects the distribution of circumferential stress.

參考文獻：

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