船舶油气爆燃火灾加强机制研究

发布时间：2018-03-18 04:09

本文选题：船舶油气　切入点：爆燃火灾　出处：《哈尔滨工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：随着近年来国家海洋战略的大力实施及建设强大的现代化海军的需求,我国船舶行业进入了新一轮快速发展时期。船舶机舱内众多的管道油路中含有大量可燃油气,加之机舱内的高温环境,一旦发生管道泄漏,极易发生局部点火爆燃进而在各种设备的扰动作用下大大增强火灾危害,造成重大人员伤亡和财产损失,使之成为船舶安全的重要威胁之一。故研究障碍物对船舶油气爆燃火灾的加强机制,对于预防和控制船舶油气爆燃火灾具有重要现实意义。本文在总结油气爆燃规律的基础上,通过热力学、燃烧动力学和气体动力学分析,提炼出物理与数学模型,通过CFD软件结合大涡模拟方法进行求解,以期获得一般性规律和方法。首先,本文研究了障碍物因素对船舶油气爆燃火灾特征参数的影响,爆燃火焰的压力随着障碍物阻塞率的增加而先增加后减小,同时爆燃火焰的速度随着阻塞率的增加而一直增加;增加障碍物厚度对火焰速度的影响从不变到逐渐变慢,火焰压力先增加后减小;不断增加的障碍物数量使爆燃火焰的速度及压力都不断增加;在障碍物分布间距的研究中,不断增加的首距使火焰压力与速度都不断增加,在接近障碍物内径的第二间距处取到了最大的火焰速度,同时火焰压力随着第二间距的增加而一直增加,分析结果表明障碍物诱导的湍流与火焰间的正反馈作用是障碍物加强油气爆燃的根本原因。其次,本文再对通道因素对船舶油气爆燃火灾特征参数的影响进行了进一步探讨,随着通道长度的增加,火焰压力及速度都增加并趋于收敛;在同阻塞率条件下不断增加通道直径时,火焰压力及速度都大幅降低;在通道不同位置点火时,点火点左侧火焰锋面向左波动传播,火焰压力和速度呈现较大差别。最终结果表明障碍物和通道对油气爆燃都有重要影响。
[Abstract]:With the implementation of national marine strategy and the demand of building a powerful modern navy in recent years, China's shipbuilding industry has entered a new period of rapid development. There are a lot of combustible oil and gas in many pipeline routes in the ship cabin. In addition to the high temperature environment in the engine room, once the pipeline leaks, it is easy to ignite local fire and deflagration, which greatly enhances the fire hazard under the disturbance of various equipment, resulting in heavy casualties and property losses. Therefore, it is of great practical significance to study the strengthening mechanism of obstacles to oil and gas deflagration fire in ship, which is of great practical significance to prevent and control the oil and gas deflagration fire in ships. Based on the summary of the laws of oil and gas deflagration, this paper summarizes the rules of oil and gas deflagration. Through thermodynamics, combustion dynamics and gas dynamics analysis, the physical and mathematical models are abstracted and solved by CFD software combined with the large eddy simulation method in order to obtain the general laws and methods. In this paper, the influence of obstacle factors on the characteristic parameters of ship oil / gas deflagration fire is studied. The pressure of deflagration flame increases first and then decreases with the increase of blockage rate, and the velocity of deflagration flame increases with the increase of blockage rate. The influence of increasing the thickness of obstacles on the flame velocity changes from constant to slow, the flame pressure increases first and then decreases; the increasing number of obstacles increases the velocity and pressure of deflagration flame; in the study of the distance between obstacles, With the increasing of the first distance, the flame pressure and velocity are increased, the maximum flame velocity is obtained at the second distance near the inner diameter of the obstacle, and the flame pressure increases with the increase of the second distance. The results show that the direct feedback between the turbulence induced by obstacles and the flame is the fundamental reason for the enhancement of hydrocarbon deflagration. Secondly, the influence of the passage factor on the characteristic parameters of the ship's oil and gas deflagration fire is further discussed in this paper. With the increase of channel length, the flame pressure and velocity increase and converge. When the diameter of the channel increases with the increase of channel diameter, the flame pressure and velocity decrease significantly. The flame pressure and velocity of the left flame-front fluctuate and propagate to the left, and the final results show that obstacles and channels have important effects on the deflagration of oil and gas.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U698

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