【摘要】 本文先分析 Klebanoff and Dieml（1952年）大量的实验结果,并参考 Coles（1956年）所引用的一些实验结果,得到了平板湍流边界层中内层和外层的速度分布及其厚度,然后根据这些关系式对边界层能量方程积分求解。内层湍流的速度分布为如下的对数定律:u⁺=5.75log y⁺+B。在本文中 B 为 Reynolds数的函数,当 Reynolds 数增大时,B 增大。例如当 R_θ=10⁵,时,μ⁺=5.75log y⁺+5.12。关于外层湍流的速度分布,本文认为仍可用如上的对数定律来表示,但各项系数有所不同,即可表示为:u⁺=10.4log y⁺-D其中 D 也随 Reynolds 数的增大而增大。例如当 R_θ=10⁵时,μ⁺=10.4log y⁺-8.78。根据各层速度分布表示式的两两交点可决定各层的厚度,层流底层的厚度 y_l⁺及内层湍流的厚度y_i⁺分别为:（?）例如当 R_θ=10⁵时,y_l⁺=11.03,y_i/δ=0.257。根据以上结果,对能量方程中的摩擦功项分三层进行了计算,得到了 R_x～R_θ的关系R_x=63R_θ^11/8/（logR_θ+0.211）^0.94。上式与 Klebanoff and Diehl 的实验比较,得到比现有类似公式更为满意的结果。更多还原

【Abstract】 After analysing the extensive experimental data of Klebanoff andDiehl （1952）,we obtain the expressions of velocity distribution andthe thickness of different regions in the flat plate turbulent boundarvlayer.Velocity distribution of inner region is well known as the logarithmiclaw:u⁺=5.75 log y⁺+B.But the term B is no longer a constant,it is afunction of Revnolds number.Its value increases when Reynolds numberincreases.For more easily integrating the energy equation,we find thatvelocity distribution of outer region can also be expressed by a logarithmiclaw:u⁺=10.4 log y⁺-D,but with a different slope 10.4 instead of 5.75in the former similar equation of inner region.The velocity distributionin laminar sublayer is expressed by a linear law as usual:u⁺=y⁺.Fromthe intersecting points of these three expressions,the thickness of differentregions can be determined.Then the friction-term of the energy equationmay be calculated after dividing the turbulent boundary layer into threeregions.Finally we obtain the R_x～R_θ relation of the formR_x=(63R_θ^I（1/8）/（logR_θ+0.211）^0.94This expression agrees better with experiment of Klebanoff and Diehlthan that deduced from the 1/7 law.更多还原