中文摘要：

采用正交试验设计方法,以未使用过的润滑油为工质,对高Pr数流体在肋叉排列三维内肋管中的流动特性进行了试验研究.结果表明：采用肋叉排列的三维内肋管可使高Pr数流体在较低的雷诺数下实现从层流向湍流的转变,其临界雷诺数Recr范围为100～200.在工程应用中,采用三维内肋管进行高黏度流体换热,容易使流动处于换热系数较高的湍流区获得明显的强化换热效果.用最小二乘法对试验数据进行多元线性回归,得到了肋叉排列的三维内肋管肋形结构对流态转变的临界雷诺数的准则方程式,为后续的分区强化传热提供参考.

英文摘要：

The performance of flow resistance of high Prandtl number fluid within three-dimensional internally crossing-finned tube was investigated with orthogonal experimental method.Fresh oil was selected as work medium in this study.Results showed that obvious low critical Reynolds numbers at the range of 100 to 200 were attained within all experimental tubes,which indicated 3-D internally crossing-finned tubes could accelerate the transform from laminar flow to turbulent flow.The empirical equation on critical Reynolds number within 3-D internally crossing-finned tubes was obtained using linear minimal dual multiply method.The optimal configurations of 3-D internally crossing-finned tube for the flow transition were also discussed according to experimental results.This study offered the reference for the later study on heat transfer of 3-D internally crossing-finned tubes.