摘要
目的食道的主要功能与力学性质密切相关 ,通过对食道进行拉伸、充压、扭转 ,定量地测量食道被动扭转生物力学特性。方法应力应变的计算采用薄壁筒模型 ,认为食道在轴向和环向两个方向的应力沿壁厚均匀分布 ,而忽略径向的应力和其他横向剪应力。结果实验表明 ,在一定的伸长比和内压下 ,扭矩和扭转角度呈线性关系 ,剪切模量可由扭矩、扭转角度以及在此状态下的极惯量计算而得 ;剪切模量不随剪应力和剪应变的变化而变化 ,改变轴向伸长比和透壁压将使剪切模量产生变化。结论在伸长比一定的充压过程中 ,剪切模量与透壁压、轴向应力呈线性关系。在透壁压一定的伸长过程中 ,剪切模量与轴向伸长比、轴向应变呈非线性关系。
Objective This work is focused on providing quantitative measurement of passive biomechanical torque properties of rat esophagus. Method Rat esophagus was treated as a membrane when calculating the stress and strain.The longitudinal and circumferential stresses were considered to be evenly distributed along the wall thickness while the radial stress and other transverse shear stresses were ignored. Result The torque vs twist-angle relation was approximate by linear at a specific pressure and longitudinal stretch ratio. Thus, the shear modulus can be computed by the torque, twist angle and polar moment of inertial at this state. However, the shear modulus varies greatly with the change of inflation pressure to longitudinal stretch ratio. Conclusion In the process of inflation at a fixed longitudinal stretch ratio, the shear modulus is linear as a function of the transmural pressure and longitudinal stress. When transmural pressure is fixed, the sheer modulus is non-linear as a function of the longtitudinal stretch ratio and strain.
出处
《航天医学与医学工程》
CAS
CSCD
北大核心
2004年第2期126-129,共4页
Space Medicine & Medical Engineering
基金
国家自然科学基金资助项目 ( 10 0 72 0 0 6)
关键词
食道
生物力学特征
扭转模量
应变能方程
esophagus
biomechanical properties
torque modulus
strain energy function
