Abstract Dependence of boundary layer thickness on layer height in laminar and transient regimes is studied for convection from localised heat source with an open surface. The measurements of Nusselt number and characteristic frequency of thermal plume formation are done for a wide range of Rayleigh number, different Prandtl numbers and different aspect ratios. The obtained results prove that for the developed (but not turbulent) convective flow the boundary layer thickness is almost independent of the layer height and it is mainly defined by applied temperature difference and physical properties of the fluid.

中文翻译：

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扩展局部加热器的边界层厚度对层高的依赖性

摘要 针对来自具有开放表面的局部热源的对流，研究了层流和瞬态状态下边界层厚度对层高的依赖性。Nusselt 数和热羽流形成的特征频率的测量是针对大范围的 Rayleigh 数、不同的 Prandtl 数和不同的纵横比进行的。获得的结果证明，对于发展的（但不是湍流的）对流，边界层厚度几乎与层高无关，它主要由施加的温差和流体的物理性质决定。