FLUENT脉冲爆轰发动机的DDT过程数值模拟
时间:2018-07-04 16:49 来源:毕业论文 作者:毕业论文 点击:次
| 摘要脉冲爆轰发动机作为利用脉冲爆轰推进的新型发动机，具有工作范围宽、燃烧效率高、比冲高、耗油率低等优点，是未来航空航天领域推进系统发展的一个重要课题，其中燃烧转爆轰（DDT）过程是PDE研究的关键技术。本文对脉冲爆轰发动机的DDT过程进行数值模拟，主要进行以下工作：25158 a）对光滑圆管内的DDT过程进行数值模拟。首先在一倍管径处点火，分析燃烧转爆轰的过程。之后对不同的点火位置进行模拟，得出在一倍管径处点火DDT距离最短。 b）对带障碍物的圆管内的DDT过程进行数值模拟。发现加入障碍物后，会在障碍物拐点处产生热点，对DDT过程有较大影响。之后改变障碍物阻塞比，发现阻塞比越大，DDT距离越短。 关键词 脉冲爆轰发动机 燃烧转爆轰 数值模拟 热点 毕业论文设计说明书外文摘要 Title Numerical simulation of deflagration-to-detonation transition in pulse detonation engine Abstract As a new concept of propulsive engine, pulse detonation engine (PDE) uses intermittent detonation to generate thrust. Compared with current propulsive engines, PDE has a wide working range, high thermodynamic efficiency, high specific impulse and low fuel consumption. Study on DDT is one of key techniques in PDE which has been developed into an important subject in the field of aerospace propulsive system. In this paper, DDT courses of PDE have been studied using numerical simulation, mainly include following aspects Abstract In this paper, some work has been done on numerical simulation of DDT process in PDE and results have been achieved as followed: a) The DDT process in a smooth duct has been numerically simulated under varying ignition location. Based on the simulating results, some research work on phases of DDT process has been done. Results show that DDT distance is minimized with the ignitor located one combustor diameter from the head wall. b) The DDT process in obstructed channels has been numerically simulated under varying obstacle blockage ratio. Results show that, hot spots will be generated in the corner of obstacle, which has a great effect on DDT process. And DDT distance decreases with increased blockage ratio. Keywords Pulse detonation engine Deflagration-to-detonation transition Numerical simulation Hot spot 目 次 1 绪论 1 1.1 课题研究背景及意义 1 1.2 脉冲爆轰发动机概念 1 1.3 研究概况及关键技术 3 1.4 本文主要研究内容 6 2 爆轰的物理基础 7 2.1 爆轰波与缓燃波的区别 7 2.2 爆轰波的传播 7 2.3 爆轰波结构 10 3 数值计算方法 13 3.1 基本假设 13 3.2 数学模型 13 3.3 求解方法 17 4 光滑圆管内DDT过程数值模拟 18 4.1 引言 18 4.2 计算模型 18 4.3 数值模拟结果 18 4.4 不同点火位置的DDT过程模拟 24 4.5 小结 31 5 带障碍物的圆管内DDT过程数值模拟 32 5.1 引言 32 5.2 计算模型 32 5.3 数值模拟结果 32 5.4 不同障碍物阻塞比的DDT过程模拟 38 (责任编辑：qin) |