Predictability of detonation wave dynamics in gases: experiment and model development

气体中爆轰波动力学的可预测性：实验和模型开发

• 批准号: RGPIN-2017-04322
• 负责人: Radulescu, Matei
• 金额: $ 4.01万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=709230
• 关键词: Predictability; detonation; wave; dynamics; gases

Detonation waves are self-sustained supersonic combustion waves. These waves can be sustained in most energetic media including reactive gases. For safety applications, it is thus desirable to have the predictive capability for the eventual ignition of a detonation wave and for its propagation limits when different mitigation strategies are used. Likewise, propulsion applications of detonation waves (e.g., rotating detonation engines, pulse-detonation engine, oblique detonation engine) require accurate control of the wave initiation and stability. For all practical purposes, the detonation behavior needs to be predicted on scales on the order of meters (engine geometry, detonation arrestors, industrial facility configuration, etc...), whereas the detonation wave thickness phenomena occur at scales comparable to the molecular mean free path, i.e. less than a micron. The detonation phenomenon is thus an inherent multi-scale problem, with multi-scale physics. Adequate predictability of detonation wave dynamics is not currently possible at engineering scales. Achieving such predictability is the main thrust of my long-term research program on gaseous detonations. The research program applied for is a state-of-the-art multi-scale experimental and theoretical investigation of the phenomena controlling the reaction rates in detonation waves. Well-posed experiments at various scales of observations (the micro, meso and engineering scales) will permit to formulate and calibrate proposed closure models. At small scales, the influence of non-equilibrium effects and stochasticity stemming from molecular fluctuations will be studied in thermal ignition problems and compared with carefully designed experiments of critical ignition. At the meso-scale, our recently proposed Large Eddy Simulation strategy aimed at properly addressing both auto-ignition and turbulent mixing will be calibrated from the micro-scale experiments and simulations and tested against meso-scale dynamics of unstable detonation limits. Finally, the meso-scale experiments and simulations will permit the development and calibration of macro-scopic models at engineering scales for the appropriate global reaction rate in detonation waves. The outcome of the proposed research program is two-fold. Firstly, the development of a predictive capability of detonation related problems at the macro-scale engineering level through a bottom-up approach will find use in the prediction of such phenomena in the propulsion technology development and petro-chemical safety assessments. Secondly, and most importantly, it will provide training to students with the state-of-the-art solution methodologies in the field.

爆轰波是一种自持的超音速燃烧波。这些波可以在包括反应性气体在内的大多数高能介质中持续存在。因此，对于安全应用，当使用不同的缓解策略时，希望能够预测最终引爆的爆震波及其传播极限。同样，爆轰波的推进应用(如旋转爆震发动机、脉冲爆震发动机、斜爆轰发动机)需要准确控制波的起爆和稳定性。出于所有实际目的，爆轰行为需要在米的尺度上进行预测(发动机几何形状、防爆器、工业设施配置等)，而爆轰波厚度现象发生在与分子平均自由程相当的尺度上，即小于一微米。因此，爆炸现象是一个固有的多尺度问题，具有多尺度物理学。爆震波动力学的充分可预测性目前在工程规模上是不可能的。实现这样的可预测性是我关于气体爆炸的长期研究计划的主旨。 申请的研究项目是对爆轰波中的反应速度控制现象进行最先进的多尺度实验和理论研究。各种观测尺度(微观尺度、中观尺度和工程尺度)的良好实验将允许制定和校准拟议的关闭模型。在小尺度上，分子涨落引起的非平衡效应和随机性的影响将在热点火问题中进行研究，并与精心设计的临界点火实验进行比较。在细观尺度上，我们最近提出的旨在正确处理自燃和湍流混合的大涡模拟策略将通过微尺度实验和模拟进行校准，并针对不稳定爆轰极限的细观动力学进行测试。最后，中尺度实验和模拟将允许在工程尺度上开发和校准合适的爆轰波全球反应速率的宏观模型。 拟议的研究计划的结果是双重的。首先，通过自下而上的方法在宏观工程水平上开发与爆轰相关问题的预测能力，将在推进技术开发和石化安全评估中用于预测此类现象。其次，也是最重要的是，它将向学生提供该领域最先进的解决方案方法的培训。