非均匀可激发介质中的稀密螺旋波  

Sparse and dense spiral waves in heterogeneous excitable media

作　　者：董丽芳[1] 白占国[1] 贺亚峰[1] 

机构地区：[1]河北大学物理科学与技术学院,河北省光电信息材料重点实验室,保定071002

出　　处：《物理学报》2012年第12期124-130,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10975043);河北省自然科学基金(批准号:2010000185);河北省教育厅重点项目(批准号:ZD2010140)资助的课题~~

摘　　要：在非均匀可激发介质中,采用Barkley模型数值模拟了稀螺旋波和密螺旋波,并对二者的动力学行为随参数的变化进行了研究.结果发现:稀螺旋波的旋转频率随参数b的增加迅速减小,之后趋于饱和,显示出不同于密螺旋波的行为;两种螺旋波的周期和波长随参数ε和非均匀区域尺寸R的增加而增加,相对稀螺旋波而言,密螺旋波的性质对R的依赖更为敏感;稀螺旋波端点的波速随R的增加而减小,与密螺旋波波速变化趋势相反.另外,由于非均匀区域的影响,当ε或b超过某一临界值时,螺旋波臂上出现缺陷点.Dynamic behaviors of sparse and dense spirals are investigated numerically based on a Barkley model in heterogeneous excitable media. It is found that the rotating frequency of sparse spiral wave decreases rapidly with b increasing and then tends to saturation, which is different from that of dense spiral wave. The period and wavelength of dense spiral wave increase with the increase of parameter e or the size/~ of localized inhomogeneity, which depends more sensitively on the size R than those of sparse sprial wave. The change of the speed of dense spiral wave tip with R is opposite to that of the sparse spiral wave tip. In addition, inhomogeneous effect gives rise to a defect point in arm of each of the two spiral waves when e or b increases above a critical value.

关 键 词：螺旋波 非均匀区域 可激发介质 动力学行为 

分 类 号：O415[理学—理论物理]