Simulating Urban Air Pollution In The Lab

近年来，越来越多的证据表明，空气污染的健康风险，每年导致全球数百万人死亡，英国数万人死亡。这项研究旨在提高我们对城市空气污染和风场模式进行建模的能力，以便为影响人们健康和福祉的政策提供信息。这些科学进步将通过应用先进的航空航天方法来实现，包括比例模型空气动力学测试、真实建筑中的现场测量以及将测量与计算流体动力学模型相耦合的数据驱动方法。这些新的方法有望揭示对工业和城市污染源污染物扩散和传输的理解，并提高我们在对城市流量至关重要的地方和城市尺度上监测、模拟和控制空气污染的能力。这些技术使我们能够填补关于局部流动模式对行人舒适性、建筑优化、空气质量和宏观天气预报影响的知识空白。比例模型空气动力学实验将集中于使用最先进的光学诊断工具来揭示风模式，这是建筑模型内和周围污染扩散的机制。在这项合作的第一部分，利用循环水隧道中的比例模型，以染料作为空气污染的代理，开发了新颖的实验。这些实验成功地复制了大气边界层条件，并强调了高层建筑在加强城市树冠外地面污染的垂直输送方面的重要性。在这一扩展中，将使用粒子跟踪技术和透明城市模型来揭示街道水平和城市峡谷内的流动特征的动态。实验室测量将与真实建筑的现场测量相补充。这是通过使用南安普顿大学校园建筑的跨学科合作实现的。这些测量将是验证模型的机会，并将纳入新的数据驱动方法，这些方法将用于分析结果并将其转化为行业影响。数据驱动的方法旨在降低湍流模型的复杂性，填补缺失的信息，并揭示流动的物理特性。城市空气动力学提供了一种非常适合这种方法的新应用，因为关键的流动特征预计将由地形和新奇的流动特性固定，因为流动的速度和浓度特性都需要在物理中捕捉到。通过与风力工程界的密切合作，将继续促进对工业的影响。将继续通过模拟南安普顿市空气污染的案例研究来支持对政策的影响，并为国家战略文件作出贡献。通过这一奖学金所实现的公众宣传也突出了空气动力学不仅与飞机和赛车有关，而且许多人都可以在这一领域工作，展示了“城市空气动力学”作为一个新兴的研究领域。这一奖学金的扩展是一个机会，可以在这些基础上扩大我们发现的新科学的跨学科适用性，并将结果转化为与政策和行业相关的进一步影响。

There has been increased evidence in recent years about the health risks of air pollution, which contribute to millions of deaths globally and tens of thousands of UK deaths annually. This research is about improving our ability to model urban air pollution and wind patterns to inform policy affecting people's health and wellbeing. These scientific advances will be achieved by applying advanced aerospace approaches including scale-model aerodynamic testing, in-situ measurements in real-life buildings, and data-driven methods coupling measurements to computational fluid dynamics models. These novel approaches promise to reveal understanding of the dispersion and transport of pollutants from industrial and urban sources and advance our ability to monitor, model, and control airborne pollution at the local and city scales critical for urban flows. These techniques allow us to fill a gap in our knowledge about the influence of local flow patterns to pedestrian comfort, building optimisation, air quality, and macroscale weather prediction. The scale-model aerodynamics experiments will focus on using state-of-the-art optical diagnostic tools to reveal the wind patterns that are the mechanisms of pollution dispersion in and around building models. In the first part of this fellowship, novel experiments were developed using scale models in a recirculating water tunnel with dye as a proxy for air pollution. These experiments successfully replicated atmospheric boundary layer conditions and highlighted the importance of tall buildings in enhancing vertical transport of ground-level pollution out of the urban canopy. In this extension, particle tracking techniques and transparent city models will be employed to reveal the dynamics of the flow features at street level and within urban canyons.The lab measurements will be supplemented by in-situ measurements of real-life buildings. This is made possible by an interdisciplinary collaboration using University of Southampton campus buildings. These measurements will be an opportunity to validate models and will feed into the new data-driven approaches that will be used to analyse the results and translate them into industry impact. Data-driven methods aim to reduce the complexity of the turbulent flow models, fill in missing information, and reveal physics of the flow. Urban aerodynamics provides a novel application well-suited to this approach as key flow features are expected to be anchored by the terrain and novel as both velocity and concentration properties of the flow need to be captured in the physics.Impact to industry will continue to be fostered by working closely with the wind engineering community. Impact to policy will continue to be supported through case studies simulating air pollution in the city of Southampton and contributing to national strategy documents. The public outreach made possible through this fellowship also highlights that aerodynamics is not only relevant to aeroplanes and race cars and that a diversity of people can work in this field, showcasing "urban aerodynamics" as an emerging field of research.This fellowship extension is an opportunity to build on these foundations to broaden the inter-disciplinary applicability of the new science we uncover and translate the results into further policy-relevant and industry-relevant impact.