摘要船舶空间有限,各种舱室设备繁多,导致船舶上环境复杂,较多狭窄空间。因结 构紧凑,没有很多开阔空间,通风效果极差。一旦发生火灾后,对人体有害的烟气难 以排除,环境内的温度极高,不易扩散到船体外部,很容易发生轰爆。对人员,财产 安全产生巨大威胁,船舶消防灭火尤为重要。细水雾作为带替卤代烷灭火剂的出现有 着极大的优点。86015
本文采用火灾动力学模拟工具 FDS 软件,建立了船舶走廊的狭窄空间内火灾模 型,研究细水雾对抑制船舶狭窄空间火灾的效果。通过对有、无细水雾状态下火灾发 展过程中的火焰状态、烟气浓度、速度、温度等数值进行对比分析,得到:
(1)细水雾可以破坏火焰的稳定形态,抑制火焰的燃烧;
(2)细水雾可以隔绝烟气与热辐射,防止烟气和热量的大规模扩散;
(3)细水雾可以通过快速汽化带走热量,降低温度;
(4)细水雾可以扰乱周边速度场,控制热流,抑制火焰扩散。 因此,细水雾射流式狭窄空间灭火的有力工具。
毕业论文关键字:FDS;狭窄空间;灭火;细水雾;数值模拟
Abstract Limited space ship, wide variety of equipment cabin, resulting in the marine environment is very complex, the more narrow space。 Due to compact structure, no a lot of open space, poor ventilation effect。 In the event of a fire, of smoke is harmful to human body it is difficult to get rid of, within the environment of high temperature not easy to spread to external hull, it is prone to detonation。 Of personnel, property safety produce a great threat, ship fire fighting is particularly important。 Water mist as belt for the emergence of halon fire extinguishing agent has a great advantage。
The fire dynamics simulation tool software FDS, establish the model of ship corridor in the narrow space of the fire, the study of effects of water mist on the inhibition effect of the narrow space of a ship fire。 Through the with and without water mist fire in the process of the development of flame, flue gas concentration, velocity and temperature values were compared and analyzed。 It is found that the
(1)the fine water mist can destroy the flame's stable form and restrain the combustion of the flame;
(2)water mist can be isolated from the smoke and heat radiation, to prevent the spread of smoke and heat;
(3)the fine water mist can take the heat by the fast vaporization, reduce the temperature;
(4)the fine water mist can disturb the surrounding velocity field, and enhance the air convection to cool down。
Therefore, the water mist jet is a powerful tool for the narrow space fire。
Keyword:FDS;narrow space;fire;water mist;numerical simulation、
目 录
第一章 绪论 1
1。1 研究目的及意义 1
1。2 研究现状 2
1。3 火灾参数 4
1。4 论文主要研究内容 7
1。5 本章小结 7
第二章 数学模型 8
2。1 基本守恒方程组 8
2。2 低马赫数假设 9
2。3 燃烧与反应方程 9
2。4 液滴模型 10
2。5 本章小结 11
第三章 物理模型建立 12
3。1 模型建立