力学载荷促进软骨传质的仿真研究
发布时间：2019-06-17 08:48
【摘要】：关节软骨呈乳白淡蓝色,表面光滑且半透明,有光泽,具有多种多样无可替代的独特功能和重要作用。但是关节软骨是临床疾病多发部位,并且关节软骨自身恢复能力低。关节软骨缺损经常造成关节功能障碍等疾病,从而影响人们的正常活动和日常生活。故对软骨传质的研究成为了国内外的热点。正常软骨的传质过程需要在一定的外界载荷作用下进行。本文采用有限元数值模拟分析关节软骨在力学载荷作用下的传质,根据仿真结果研究不同载荷作用下传质的规律,为临床疾病治疗和组织修复等提供科学依据。根据传质理论中的斐克第二定律,质量守恒定律以及传热和传质在数值上的等效,提出了软骨传质的仿真方案,运用有限元软件ANSYS建立软骨模型,对模型施加静态压缩,并将仿真结果与实验结果对比,两者具有较好的相关性,表明了模拟方法的正确性。基于静态压缩时的仿真模型,研究动态压缩对软骨传质的影响以及动态压缩参数对传质的影响。结果表明:①软骨施加载荷之后,软骨传质速度比静置时加快了很多。②动态压缩载荷作用下,在初期软骨传质在深层和中间层的速度十分缓慢,而浅表层的传质速度很快,但随着时间的增加,浅表层浓度增长缓慢,趋于稳定的浓度值,而中间层和深层增速加快。③压缩幅值相同时,静态压缩与动态压缩相比,软骨内部溶质更容易扩散。④动态压缩振幅增加时,软骨内溶质浓度随时间均为上升趋势,浅表层增加明显,但随着幅值的增加,溶质扩散受到抑制,且幅值越大,抑制作用越明显。⑤动态压缩频率增加,有利于软骨各层溶质扩散,频率越大,扩散速度增加越明显,浅表层变化明显。对滑动载荷作用下软骨传质规律进行研究,得出以下结论:①在初期软骨传质在深层的速度相对缓慢,而在中间层和浅表层的传质速度较快。但随着时间的增加,浅表层浓度增长缓慢,趋于稳定的浓度值,中间层增速也有所下降,然而深层传质速度的增加十分明显。②滑动载荷作用压缩量增加时,软骨内溶质浓度随时间均为上升趋势,但随着压缩量的增加,对溶质扩散有抑制作用,其中中间层的抑制作用最大,深层的抑制作用最小。③滑动速度的增加,有利于软骨各层溶质扩散,其中中间层和深层的扩散速度增加十分明显。仿真结果为今后进一步研究提供了一定的理论基础。研究不同模型对仿真结果的影响,发现:①在运用ANSYS进行仿真时,分层和不分层对软骨传质研究的影响很小。为了操作简便,提高效率,可以不对软骨进行分层。②在运用ANSYS进行仿真时,三维模型与二维模型存在差异,由于三维模型的建立和载荷的施加更接近于真实情况,所以在研究软骨传质时,应优先考虑三维模型,提高计算的准确度。仿真结果为下一步仿真模拟时模型的选择提供了一定的基础。
[Abstract]:The articular cartilage is milky white and light blue, the surface is smooth and translucent, has a luster, and has a variety of irreplaceable unique functions and important functions. But the joint cartilage is a multiple part of the clinical disease, and the self-recovery ability of the joint cartilage is low. Joint cartilage defects often cause joint dysfunction and other diseases, thus affecting the normal activity and daily life of people. Therefore, the study of mass transfer of cartilage has become a hot spot at home and abroad. The mass transfer process of the normal cartilage needs to be carried out under a certain external load. In this paper, the mass transfer of the articular cartilage under the action of mechanical load is analyzed by the finite element method, and the law of mass transfer under different loads is studied according to the simulation results, and the scientific basis for clinical disease treatment and tissue repair is provided. According to the Fick's second law in mass transfer theory, the law of mass conservation and the equivalent of heat transfer and mass transfer on the numerical value, the simulation program of the mass transfer of the cartilage was put forward. The model of the cartilage was set up by using the finite element software ANSYS, the static compression was applied to the model, and the simulation results were compared with the experimental results. The results show that the simulation method is correct. The effects of dynamic compression on mass transfer and the effect of dynamic compression on mass transfer are studied based on the simulation model of static compression. The results showed that the mass transfer rate of cartilage was much faster than that of standing. Under the effect of dynamic compressive load, the velocity of mass transfer at the initial stage in the deep layer and the middle layer is very slow, while the mass transfer speed of the shallow surface layer is very fast, but with the increase of time, the concentration of the shallow surface layer grows slowly and is stable, and the middle layer and the deep layer increase rapidly. When the compression amplitude is the same, the static compression is easier to spread than the dynamic compression. When the dynamic compression amplitude of the cartilage is increased, the concentration of the solute in the cartilage increases with the time, the superficial layer is obviously increased, but with the increase of the amplitude, the solute diffusion is inhibited, and the larger the amplitude, the more obvious the inhibition effect. The dynamic compression frequency of the cartilage is increased, which is beneficial to the diffusion of the solute in the layers of the cartilage, the higher the frequency, the more obvious the increase of the diffusion speed, and the obvious change of the superficial layer. It is concluded that the mass transfer of cartilage in the initial stage is relatively slow at the initial stage, and the mass transfer rate between the intermediate layer and the shallow surface layer is fast. However, with the increase of time, the growth of the shallow surface layer is slow, the concentration value of the stabilization is stable, and the growth of the intermediate layer is also decreased, but the increase of the deep mass transfer rate is very obvious. In addition, the concentration of the solute in the cartilage increases with time, but with the increase of the amount of compression, the inhibition of solute diffusion is inhibited, and the inhibition of the intermediate layer is the largest and the inhibition of the deep layer is the least. The increase of the sliding speed of the cartilage is beneficial to the diffusion of the solute in each layer of the cartilage, and the diffusion speed of the middle layer and the deep layer is obviously increased. The simulation results provide a theoretical basis for further research in the future. The effects of different models on the simulation results are studied. In order to be simple and convenient to operate, the efficiency can be improved, and the cartilage can not be layered. In the case of simulation by using ANSYS, the three-dimensional model is different from the two-dimensional model. Because the establishment of the three-dimensional model and the application of the load are closer to the real situation, the three-dimensional model should be taken into consideration when studying the mass transfer of the cartilage, and the accuracy of the calculation is improved. The simulation results provide a basis for the selection of the model when the next simulation is simulated.
【学位授予单位】：天津理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R684;TP391.9
本文编号：2500864
[Abstract]:The articular cartilage is milky white and light blue, the surface is smooth and translucent, has a luster, and has a variety of irreplaceable unique functions and important functions. But the joint cartilage is a multiple part of the clinical disease, and the self-recovery ability of the joint cartilage is low. Joint cartilage defects often cause joint dysfunction and other diseases, thus affecting the normal activity and daily life of people. Therefore, the study of mass transfer of cartilage has become a hot spot at home and abroad. The mass transfer process of the normal cartilage needs to be carried out under a certain external load. In this paper, the mass transfer of the articular cartilage under the action of mechanical load is analyzed by the finite element method, and the law of mass transfer under different loads is studied according to the simulation results, and the scientific basis for clinical disease treatment and tissue repair is provided. According to the Fick's second law in mass transfer theory, the law of mass conservation and the equivalent of heat transfer and mass transfer on the numerical value, the simulation program of the mass transfer of the cartilage was put forward. The model of the cartilage was set up by using the finite element software ANSYS, the static compression was applied to the model, and the simulation results were compared with the experimental results. The results show that the simulation method is correct. The effects of dynamic compression on mass transfer and the effect of dynamic compression on mass transfer are studied based on the simulation model of static compression. The results showed that the mass transfer rate of cartilage was much faster than that of standing. Under the effect of dynamic compressive load, the velocity of mass transfer at the initial stage in the deep layer and the middle layer is very slow, while the mass transfer speed of the shallow surface layer is very fast, but with the increase of time, the concentration of the shallow surface layer grows slowly and is stable, and the middle layer and the deep layer increase rapidly. When the compression amplitude is the same, the static compression is easier to spread than the dynamic compression. When the dynamic compression amplitude of the cartilage is increased, the concentration of the solute in the cartilage increases with the time, the superficial layer is obviously increased, but with the increase of the amplitude, the solute diffusion is inhibited, and the larger the amplitude, the more obvious the inhibition effect. The dynamic compression frequency of the cartilage is increased, which is beneficial to the diffusion of the solute in the layers of the cartilage, the higher the frequency, the more obvious the increase of the diffusion speed, and the obvious change of the superficial layer. It is concluded that the mass transfer of cartilage in the initial stage is relatively slow at the initial stage, and the mass transfer rate between the intermediate layer and the shallow surface layer is fast. However, with the increase of time, the growth of the shallow surface layer is slow, the concentration value of the stabilization is stable, and the growth of the intermediate layer is also decreased, but the increase of the deep mass transfer rate is very obvious. In addition, the concentration of the solute in the cartilage increases with time, but with the increase of the amount of compression, the inhibition of solute diffusion is inhibited, and the inhibition of the intermediate layer is the largest and the inhibition of the deep layer is the least. The increase of the sliding speed of the cartilage is beneficial to the diffusion of the solute in each layer of the cartilage, and the diffusion speed of the middle layer and the deep layer is obviously increased. The simulation results provide a theoretical basis for further research in the future. The effects of different models on the simulation results are studied. In order to be simple and convenient to operate, the efficiency can be improved, and the cartilage can not be layered. In the case of simulation by using ANSYS, the three-dimensional model is different from the two-dimensional model. Because the establishment of the three-dimensional model and the application of the load are closer to the real situation, the three-dimensional model should be taken into consideration when studying the mass transfer of the cartilage, and the accuracy of the calculation is improved. The simulation results provide a basis for the selection of the model when the next simulation is simulated.
【学位授予单位】：天津理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R684;TP391.9
【参考文献】
相关期刊论文 前2条
1 董江峰;于杰;陈维毅;;力学刺激对关节软骨基质代谢的影响[J];国际骨科学杂志;2006年06期
2 邱郡;张文光;吴刚;王成焘;;关节软骨的仿生设计[J];生物医学工程学杂志;2008年01期
相关硕士学位论文 前1条
1 范振敏;滚动载荷条件下软骨传质过程的研究[D];天津理工大学;2012年
，本文编号：2500864
本文链接：https://www.wllwen.com/yixuelunwen/waikelunwen/2500864.html
最近更新
教材专著
