中文摘要：

对不同长度及不同数量的高分子链在微直通道及微缩通道中的流动进行了模拟与分析.研究表明,高分子链的伸展状态与微通道的形状密切相关,微直通道中高分子链能较充分地伸展,方形微缩通道中高分子链未能充分伸展,而斜坡微缩通道中高分子链的伸展状态介于微直通道与方形微缩通道之间.高分子的存在对微通道系统的温度没有明显影响,对密度与水平流动速度有较明显的影响.高分子链的运动直接影响到周围的简单流体粒子,降低其周围流体粒子的流动速度,对密度与速度产生局部扰动,形成＂拖曳＂现象.高分子链分布越密集,长度越长,高分子链的拖曳现象越明显.

英文摘要：

The transport and conformation of macromolecules in micro-channels were studied by using the dissipative particle dynamics （DPD） and finite extensible non-linear elastic （FENE） bead spring chains model. The dynamic behavior of macromolecules with different numbers of beads and different chain lengths in three kinds of micro-channels, straight, quadrate contraction and sloping contraction micro-channels are comparatively analyzed. It is found that macromolecules are mainly concentrated in the middle of channels. Macromolecules located near solid walls are stretched better than those in the middle of channels,which are usually coiled. The shape of micro-channel can influence the conformation and transportation of macromolecules. Straight channels can well stretch the macromolecules. Quadrate contraction channels can have negative effects in stretching the macromolecules with possible circulation flow at the corner areas. While the behavior of sloping contraction channels is between that of the straight channels and quadrate contraction channels. It is also found that macromolecule chains do not influence the temperature distribution and evolution. Instead macromolecular chains have remarkable influences on the density and velocity distribution, while the distribution and conformation of the macromolecules are closely related to the shape and geometry of the micro channels. The macromolecules tend to drag the simple DPD particles, reducing their velocity, and leading to density fluctuations. The dragging effect is more important as the number of macromoleeules or the length of the macromolecular chain increases.