【作者】 马倩；

【导师】 张敏；

【作者基本信息】 南京理工大学 ， 流体力学， 2007， 硕士

【摘要】 工业生产中经常遇到充分发展的轴向层流在环管中的流动与热交换，很多情况下这些流体表现出非牛顿流体的性质。本文研究了表观粘度函数为幂律形式的幂律流体在环管中的流动与换热情况，考虑不同的边界条件，在结构化网格和非结构化网格中数值模拟出不同流动指数的流体在不同流通区域中的速度场和温度场，给出雷诺数、摩擦因子、努谢尔数等。特别对于环管产生偏心的情况，给予了更深入的研究。区域的不对称性和非牛顿流体的本身性质，严重影响了速度及温度分布。考虑环管偏心率和半径率的影响，研究圆环半径比在0.2和0.8之间，偏心率在0和0.6之间的情况，复杂的流通区域使流动和换热的分布严重不均，引起了反常的水力及热力性质。同时对于结构化网格的计算结果和非结构化网格的计算结果进行比较，也与部分精确解进行比较，得出了比较理想的结果。上述有关方法和结论将为工程上的设计与更深入地研究提供有利的依据。更多还原

【Abstract】 Many laminar fully developed flows, that are processed in many heat exchange andflow devices with annular channels, exhibit a viscous, non-Newtonian behavior.This paper referred to the flows and the forced convection heat transfer of thepower-law fluids, and the different boundary conditions were considered. Numericalsolutions for the velocity and temperature distributions, Reynolds number, isothermalfrictions factors, and Nusselt numbers for different ducts were presented. And the instanceof inner core eccentricity was analyzed. The geometric asymmetry of the eccentric annularcross-section and the performance of the non-Newtonian were seen to have a stronginfluence on the velocity and temperature distributions. The annular ducts of varyingaspect ratios from 0.2 to 0.8, and inner core eccentricity from 0 to 0.6 were considered. Thecomplex ducts induced the non-uniformity in the velocity and the temperature field, whichproduced a significantly anomalous thermal-hydraulic performance. And the resultscomputed on unstructured grids and the solutions computed on structured grids werecontrasted, also compared with some results shown in the reference. All of these prove thatthe method and the program are correct and perfect. The methods and the conclusions ofthis paper can be helpful to the design in industry and the improved research.更多还原