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A reevaluation of assumptions in the turbulent boundary-layer equations with regard to the momentum theorem

机译：关于动量定理的湍流边界层方程中假设的重新评估

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Bidwell, J. M.;
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年度 1951
页码 1-46
总页数 46
原文格式 PDF
正文语种 eng
中图分类工业技术;
关键词
MATHEMATICAL MODELS; MOMENTUM THEORY; TURBULENT BOUNDARY LAYER; INCOMPRESSIBLE FLUIDS; LAMINAR BOUNDARY LAYER; NAVIER-STOKES EQUATION; VISCOUS FLOW;

机译：数学模型;动力学理论;湍流边界层;不可压缩的流体; LamINaR BOUNDaRY LaYER; NaVIER-sTOKEs方程;粘性流动;

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1. Errors in parametrizations of convective boundary-layer turbulent momentum mixing [J] . A. R. BROWN, A. C. M. BELJAARS, H. HERSBACH Quarterly Journal of the Royal Meteorological Society . 2006,第619期

机译：对流边界层湍流动量混合的参数化误差
2. A non-iterative method for boundary-layer equations-Part II: Two-dimensional laminar and turbulent flows [J] . Tuncer Cebeci, Jian Ping Shao International Journal for Numerical Methods in Fluids . 2003,第9期

机译：边界层方程的非迭代方法-第二部分：二维层流和湍流
3. Assessment of model assumptions and budget terms of the unsteady flamelet equations for a turbulent reacting jet-in-cross-flow [J] . Wai Lee Chan, Hemanth Kolla, Jacqueline H. Chen, Combustion and Flame . 2014,第10期

机译：湍流交叉射流的非稳态小火焰方程模型假设和预算项的评估
4. Approximate analysis of turbulent entrainment in an inclined plume using k- ε model equations based on similarity assumption [C] . Tadaharu Ishikawa, Akira Moribayashi, Fengyi Gao, Fifth International Symposium on Stratified Flows . 2000

机译：基于相似假设的k-ε模型方程对斜羽中湍流夹带的近似分析
5. Liouville and Harnack type theorems for semilinear elliptic equations and Yamabe type equations. [D] . Zhang, Lei. 2001

机译：半线性椭圆方程和Yamabe型方程的Liouville和Harnack型定理。
6. Modeling boundary-layer transition in direct and large-eddy simulations using parabolized stability equations [O] . A. Lozano-Durán, M. J. P. Hack, P. Moin -1

机译：使用抛物线稳定性方程在直接和大涡流模拟中对边界层过渡进行建模
7. This article presents a new numerical model describing the behaviour of a thermally thick wood sample exposed to high solar heat flux (above 1 MW/m2). A preliminary study based on dimensionless numbers is used to classify the problem and support model building assumptions. Then, a model based on mass, momentum and energy balance equations is proposed. These equations are coupled with liquid-vapour drying model and pseudo species biomass degradation model. By comparing to a former experimental study, preliminary results have shown that these equations are not enough to accurately predict biomass behaviour under high solar heat flux. Indeed, a char layer acting as radiative shield forms on the sample exposed surface. In addition to this classical set of equations, it is mandatory to take into account radiation penetration into the medium. Furthermore, as biomass contains water, medium deformation consecutively to char steam gasification must also be implemented. Finally, with the addition of these two strategies, the model is able to properly capture the degradation of biomass when exposed to high radiative heat flux over a range of sample initial moisture content. Additional insights of biomass behaviour under high solar heat flux were also derived. Drying, pyrolysis and gasification fronts are present at the same time inside of the sample. The coexistence of these three thermochemical fronts leads to char gasification by the steam produced from drying of the sample, which it is the main phenomenon behind medium ablation. [O] . Pozzobon, Victor, Salvador, Sylvain, Bézian, Jean Jacques 2018

机译：本文提供了一个新的数值模型，该模型描述了暴露于高太阳热通量（高于1 / MW / m2）的热厚木材样品的行为。基于无量纲数的初步研究用于对问题进行分类并支持模型构建假设。然后，提出了一种基于质量，动量和能量平衡方程的模型。这些方程式与液体蒸汽干燥模型和假物种生物质降解模型耦合。通过与以前的实验研究进行比较，初步结果表明，这些方程不足以准确预测高太阳热通量下的生物量行为。的确，在样品暴露的表面上形成了充当辐射屏蔽层的炭层。除了这套经典的方程式之外，还必须考虑到辐射向介质的渗透。此外，由于生物质中含有水，因此还必须在炭蒸气汽化后进行连续的介质变形。最后，通过添加这两种策略，该模型能够在一定范围的样品初始水分含量下暴露于高辐射热通量的情况下，正确捕获生物质的降解。还得出了在高太阳热通量下生物量行为的其他见解。样品内部同时存在干燥，热解和气化前沿。这三个热化学前沿的共存会导致样品干燥产生的蒸汽产生焦炭气化，这是介质烧蚀的主要现象。
8. Calculation of three-dimensional compressible laminar and turbulent boundary layers. An implicit finite-difference procedure for solving the three-dimensional compressible laminar, transitional, and turbulent boundary-layer equations [R] . Harris, J. E. 1975

机译：三维可压缩层流和湍流边界层的计算。求解三维可压缩层流，过渡和湍流边界层方程的隐式有限差分程序

A reevaluation of assumptions in the turbulent boundary-layer equations with regard to the momentum theorem

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