摘要烟火式气体发生器由于其产气速度快、产气温度低、体积小、使用灵活等优点,已 被广泛应用于汽车安全气囊、海上救生筏、巡飞弹翼展等民用与军事领域。过滤器作为 气体发生器的重要组件,不仅需要对颗粒残渣进行过滤,更需要对气体发生剂所产生的 高温气体进行降温。因此,本文针对金属纤维过滤器内高温气体的流动与降温过程进行 数值仿真研究,揭示金属纤维过滤器内高温气体的流动与降温特性,从而为烟火式 气体 发生器的研究提供理论指导。主要研究内容如下:79513
(1)分别建立了单金属纤维、双金属纤维以及多金属纤维绕流模型,数值模拟了不同
结构绕流的降温与流动过程,为后续深入开展过滤器内流动与降温特性研究提供基础;
(2)建立烟火式气体发生器简化物理模型,在不考虑金属纤维壁面传热的条件下,开 展过滤器内流动与降温过程的数值模拟研究,结果揭示了过滤器结构对高温气体的降温 特性;
(3)考虑金属纤维壁面传热,数值模拟了过滤器结构及纤维传热对过滤器内气体流动 与降温的影响,结果表明考虑壁面传热情况下过滤器内及标准储气罐内的降温特性得到 明显提升。
关键词 烟火式气体发生器 金属纤维过滤器 数值模拟 流动与降温特性
毕 业 设 计 说 明 书 外 文 摘 要
Title Numerical Study on the Flow and Cooling Characteristics
of Filter in Pyrotechnic Gas Generator
Abstract
Pyrotechnic gas generator has many advantages such as fast gas production rate, low gas temperature, small size, use flexible, etc。 It has been widely used in automotive airbags, maritime raft, cruise missile and other civilian and military fields。 As an important component of the gas generator, filter is not only requested to capture the particle residue, but also needs to cool the high temperature gas produced by the gas generator。 In this thesis, the numerical studies on the flow and cooling characteristics of filter in pyrotechinc are carried out, to reveal the characteristics of flow and temperature of gas in the metal fiber filter, and provides theoretical guidance for the research on the pyrotechnic gas generator。 The main content is as follows:
(1)The flow models of single metal fiber, double metal fibers and multi metal fibers are established。 Numerical simulations of the cooling and flow process of the flow around the different structures are given to provide the basis for further research on the characteristics of flow and cooling of the filter。 (2)A simplified physical model of the pyrotechnic gas generator is built。
Numerical simulation of flow and cooling process in filter is set without considering the heat transfer of metal fibers, the result of which reveals the properties of structure of the filter cooling the high temperature gas。
(3)Considering the heat transfer of metal fiber walls, the influence of the structure of the filter and the heat transfer on the flow and cooling in the filter is simulated。 The result shows that the cooling performance of the filter and the standard air storage tank can be improved on the condition of the wall heat transfer。
Keywords Pyrotechinc gas generator Metal fiber filter Numerical simulation Flow and cooling characteristics
本科毕业设计说明书 第 I 页
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