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: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=662863
• 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.

爆震波是自持的超音速燃烧波。这些波可以在包括活性气体在内的大多数高能介质中持续存在。 对于安全应用，因此需要具有在使用不同缓解策略时预测爆震波的最终点燃及其传播限制的能力。同样，爆震波的推进应用（例如旋转爆震发动机、脉冲爆震发动机、斜爆震发动机）需要对波的引发和稳定性进行精确控制。出于所有实际目的，需要在米量级的尺度上预测爆震行为（发动机几何形状、防爆震器、工业设施配置等），而爆震波厚度现象发生在与分子平均值相当的尺度上自由程，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。目前在工程规模上不可能对爆震波动力学进行充分的预测。 实现这种可预测性是我关于气体爆炸的长期研究计划的主要目标。 ******申请的研究计划是对控制爆轰波反应速率的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、中观和工程尺度）的适定实验将允许制定和校准所提出的闭合模型。 在小尺度上，将研究分子波动引起的非平衡效应和随机性对热点火问题的影响，并与精心设计的临界点火实验进行比较。在中观尺度上，我们最近提出的大涡模拟策略旨在正确解决自燃和湍流混合问题，该策略将通过微尺度实验和模拟进行校准，并针对不稳定爆炸极限的中观尺度动力学进行测试。 最后，细观尺度的实验和模拟将允许在工程尺度上开发和校准宏观模型，以获得爆炸波中适当的整体反应速率。 ******拟议研究计划的成果有两个。 首先，通过自下而上的方法在宏观工程层面开发爆炸相关问题的预测能力将可用于预测推进技术开发和石化安全评估中的此类现象。 其次，也是最重要的，它将为学生提供该领域最先进的解决方案方法的培训。