The development of turbulent pipe flow
The development of turbulent pipe flow
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湍流管流的发展
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
M. S. Chong
中科院分区：
文献类型：
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作者：
J. Doherty;P. Ngan;J. Monty;M. S. Chong
虽然湍流仍然是经典物理学最大的谜团之一，但它混乱而缺乏结构的名声正受到密切关注。现在的研究指出，湍流中存在高度有组织的大规模结构。这项研究的大部分几乎都是在所谓的完全发达的流动区域内进行的。该区域位于一个点的下游，超过该点后，流场的行为是不变的。然而，还没有确凿的证据证明一个充分发展的地区确实存在。一项文献调查发现，大多数设施都被引用为“足够长”，但没有正式的定义或充分发展的条件的文件证据被广泛接受。这项研究的目的是对从均匀进气条件到完全发展的湍流状态的流动进行详细的分析，以及对什么是完全发展的流动的准确定义。这项研究既涉及到大尺度结构的增长，也涉及到它们在水流向充分发展状态演变中的作用。随着湍流大尺度结构模型被越来越多的人接受，以往的研究还没有显示大尺度结构如何影响这一发展长度。这些目的是通过设计、开发和部署一种在管道内传输热线的托架来实现的，该托架允许在工作段内的任何流动点进行测量
Whilst turbulence still remains one of the great mysteries of classical physics, its reputation for a chaotic lack of structure is under intense scrutiny. Research now points to the existence of highly organized large-scale structures within turbulent flows. Much of this research have almost exclusively been carried out within a so called fully-developed region of flow. This region is downstream of a point beyond which the flow field’s behavior is invariant. However, it has not been conclusively proven that a fully developed region actually exists. A literature survey found that most facilities are cited as being ‘sufficiently long’, yet no formal definition or documentary evidence of the fully developed condition is widely accepted. The aim of the study is to produce a detailed analysis of the flow from the uniform inlet conditions through to the fully-developed turbulent state, along with an accurate definition of what constitutes fully developed flow. This investigation concerns the affect of both the growth of large-scale structures and their role in the evolution of the flow to the fully-developed condition. With the increasing acceptance of the turbulent large-scale structures model, previous research has not yet shown how large-scale structures affect this development length. These aims were achieved by the design, development and deployment of a carriage to transport hot-wires within the pipe allowing measurements at any stream wise point within the working section