关于烟雾层厚度与天花板结构高度在长窄空间中的变化定律的研究,其中一个端开口
Zeqi Wu1,2,3, Kunpeng Liu4,5,6, Jinyi Yang7
1College of Building Environment Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450001, China. wzq371198354@126.com.
Scientific reports
|August 22, 2024
概括
天花板结构的高度显著影响着烟雾层的厚度. 本研究定义了系数来量化理论模型的偏差,帮助建筑安全和疏散设计.
科学领域:
- 消防安全工程 消防安全工程
- 流体动力学 流体动力学
- 建筑物理 建筑物理
背景情况:
- 在长而狭窄的空间中,天花板结构的几何形状极大地影响着烟雾层的发展.
- 了解烟雾层动态对于有效的建筑消防安全和疏散策略至关重要.
研究的目的:
- 为了研究天花板结构高度对火灾烟雾层厚度的影响.
- 在天花板结构之前开发理论模型并实验验证烟雾层的行为.
- 确定影响烟雾流和层厚度偏离理论预测的因素.
主要方法:
- 在梯度流条件下进行理论分析,以获得烟雾层厚度公式.
- 小规模的实验平台来观察和测量火灾烟雾行为.
- 数值分析以探索导致观察到偏差的潜在物理机制.
主要成果:
- 实验结果与理论计算有所不同,原因是烟雾无法在天花板结构中保持梯度流.
- 定义了梯度流和厚度系数来量化这些偏差.
- 在特定的天花板结构高度 (>35厘米和<30厘米) 确定了这些系数的明显线性变化模式.
结论:
- 该研究强调了天花板结构高度在火灾烟雾动态中的重要性.
- 观察到的偏差与烟雾穿过结构的动能转化为潜在能量有关.
- 研究结果为优化建筑烟雾控制和人员疏散计划提供了宝贵的见解.
相关概念视频
Laminar Flow
1.0K
Laminar flow represents a smooth, orderly fluid motion where particles move along parallel paths, resulting in minimal mixing between layers. Streamlined particle paths characterize this flow regime and occur under conditions where viscous forces dominate over inertial forces. The distinction between laminar, transitional, and turbulent flow is primarily determined by the Reynolds number, a dimensionless quantity calculated as:
1.0K
Expansion and Contraction in Masonry Walls
948
Masonry walls are subject to slight expansion and contraction due to variations in temperature and moisture. Thermal movement in masonry is relatively straightforward to measure and plan for. On the other hand, moisture movement poses more of a challenge. New clay masonry units typically absorb water and expand over time under normal environmental conditions. Conversely, new concrete masonry units tend to shrink as they lose the excess moisture acquired during their production process.
To...
To...
948
Unsymmetric Loading of Thin-Walled Members: Problem Solving
96
The shear center of a channel section with uniform thickness, height, and width, is determined by computing the shear force in the member and calculating the moments of inertia of the sections.
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
To compute the shear forces, find the shear flow at a specific distance from the endpoint using the vertical shear and the moment of inertia values. The total shear force on the flange is calculated by integrating the shear flow from one end of the flange to the other.
Next, calculate the moments of...
96
Steady, Laminar Flow in Circular Tubes
174
Hagen-Poiseuille flow describes a viscous fluid's steady, incompressible flow through a cylindrical tube with a constant radius R. This flow profile is often applied to understand fluid transport in narrow channels, such as capillaries. It serves as a foundational example of laminar flow. In this model, cylindrical coordinates (r,θ,z) are used to describe the radial (r), angular (θ), and axial (z) dimensions within the tube. For Hagen-Poiseuille flow, the velocity profile is...
174
Unsymmetric Loading of Thin-Walled Members
101
Thin-walled members with non-symmetrical cross-sections are vital to engineering structures, offering material efficiency and structural integrity. However, unsymmetrical loading on these members leads to complex stress distributions, resulting in simultaneous bending and twisting can cause deformation or structural failure. The interaction between bending and twisting requires detailed analysis to ensure structural resilience.
The concept of the shear center is crucial in countering the...
The concept of the shear center is crucial in countering the...
101
Laminar Flow: Problem Solving
138
Laminar flow occurs when a fluid moves smoothly in parallel layers with minimal mixing and turbulence. In fluid mechanics, ensuring laminar flow within a pipe is essential for precise control of flow characteristics, especially in engineering applications. The key factor in determining whether flow remains laminar is the Reynolds number, a dimensionless quantity that depends on the fluid's velocity, density, viscosity, and the pipe's diameter. A Reynolds number of 2100 or lower...
138


