| 1. | The highest heat transfer coefficient for air flowing in the nine 3 - d ift with staggered arrangement fins is no9 tube
过渡流区和层流区的热力性能系数分别为2 . 74和1 . 06 。 |
| 2. | Piezoresistivity of ecac may involve proximity effect , microcrack and the staggered arrangements of conductive pass - ways due to shear strength of aggregates
压敏产生的原因是导电沥青混凝土试件的压缩邻近效应、微裂纹和石料间的剪切力使部分导电通路错位。 |
| 3. | Through the conventional analysis of the othorgonal testing results , we can initially determine that the best structure parameter of 3 - d ift with staggered arrangement fins
通过对正交试验结果进行常规分析，初步确定肋叉排三维内肋管的肋几何参数的优化方向。 |
| 4. | The experimental results of air heat transfer show that the relative fin height , relative fin width , relative fin pitch and density of 3 - d ift with staggered arrangement fins all have an effect on heat transfer and flow friction . especially , the effect of fin density is bigger
空气换热实验的结果表明：肋叉排三维内肋管的相对肋高、相对肋宽、相对肋间距以及肋密度均对其对流换热特性有影响，其中肋密度的影响较大。 |
| 5. | In this paper , the working fluid is air . experimental study of the nine different structure parameters of 3 - d ift with staggered arrangement fins in the reynolds number range of 250 to 30000 is performed to investigate the characteristics of heat transfer and flow friction behavior . analyses and reduces the experimental data by the least square method , obtains the nusselt and fanning friction fitting criterion equations
本文以空气为工质，在re 250 30000范围内对九根具有不同肋形结构尺寸的肋叉排三维内肋管的换热及流动特性进行了研究，并运用最小二乘法分析和处理实验数据，获得努谢尔特数，范宁摩擦系数与雷诺数，肋几何参数的准则方程式。 |
| 6. | When the punched baffle is proper in length , the small holes are in staggered arrangement and the punched ratio gradually increases from the central axis to the boundary along the baffle length , the performance of flow distribution in the plate - fin heat exchanger is effectively improved by the optimum design of header configuration
从实验对比分析中得出，当挡板小孔呈错排分布、开孔率沿挡板的中轴线向两侧逐渐增加、且总开孔率达到50 %左右的时候，在相同的入口条件下，不均匀系数由原始封头的1 . 210降至0 . 209 ，最大流速与最小流速之比由23 . 163降至1 . 756 。 |
| 7. | 3 - d ift have three fin arrangements : staggered arrangement fins , in - line arrangement fins and spiral arrangement fins . the former experimental study regressed the experimental data of all three fin arrangements and obtained the heat transfer criterion equation of 3 - d ift , while the paper sets apart the three mixed fin arrangements and applies othorgonal testing method to the 3 - d ift with staggered arrangement fins which is wide used in the engineering
原有的研究是将三种肋排列形式三维内肋管的实验数据混杂在一起进行回归得到三维内肋管的换热准则式，而本文则将原有研究中混杂不清的肋排列的三种形式区分开来，并对其中在工程中应用最广泛的肋叉排三维内肋管进行了详细的正交试验研究。 |
