AmmoSpray: fundamental spray and combustion data for a zero-carbon future

氨（NH3）是未来交通运输的一种有前途的零碳燃料。今天，交通运输每年排放约89亿吨二氧化碳。虽然某些行业（例如汽车）可以使用电池进行脱碳，但由于成本和能量密度的原因，较重的运输（海运或货运）不太可能使用电池。氨是氢的载体，（按体积计）比液氢多含50%的氢（仅液氢的储存和储存就非常耗能）。氨是所有非碳氢化合物（传统化石）燃料中能量密度最高的燃料之一。氨是特别有吸引力的，因为它可以使用成熟的哈伯-博世工艺制造，今天每年用于制造2.3亿吨氨。当由太阳能和风能供电时，氨生产可以100%可再生。这意味着氨生产可以扩展，并且可以重新利用大量现有的基础设施。全球范围内正在进行一些氨试点项目，包括能源储存，航运和货运。其中许多在英国，包括卢瑟福阿普尔顿实验室，卡迪夫大学和诺丁汉大学。然而，这些项目通常采用现有技术，这些技术是为不同的燃料（通常是化石燃料）设计的。目前还严重缺乏基础数据，无法设计针对氨的能量转换系统。这个名为AmmoSpray的项目旨在填补这一空白。AmmoSpray将首次提供有关氨喷雾到空气中的基本数据。氨可以以液体或气体的形式喷洒到空气中，这两种形式都将在本项目中进行研究。所获得的基本数据将包括喷雾破碎（液氨在喷射时如何破碎和蒸发）以及氨和空气在实际条件下如何混合。这些研究将在三种不同的测试设备上进行：1。环境条件喷雾装置2。冷驱动激波管（CDST）3.一个光学访问热推进系统（TPS）的喷雾装置是快速和廉价的运行，并将使该项目所需的实验系统的发展，大量的喷雾试验条件的测试，并将用于进行范围界定的工作，以确定项目的边界。CDST是一个独特的设施在英国，能够复制在燃烧过程中发现的条件（150 bar压力，1500 K温度），无湍流，并具有用于测试设备的空间。这将首次实现在使用中看到的条件下对氨喷雾进行成像和分解研究-关键基础数据。光学TPS测试是合乎逻辑的下一步，增加湍流，并尽可能接近“真实的”条件，同时仍然允许使用成像和测试设备。这里的关键测试将是混合，使用基于激光的技术（PLIF），以获得整个燃烧体积的氨：空气比测量。这将把早先开发的喷雾信息与它们的燃烧特性联系起来。对光学接入TPS的测试还将研究这些不同的喷雾和混合方法如何影响氨燃烧的排放物形成，其中NH3和NOx是将被测量的关键排放物。这种循序渐进的特性非常适合改进现有模型。所获得的数据将被编码到由项目合作伙伴Convergent Science提供的商业建模软件（计算流体动力学（CFD））。其CONVERGE CFD软件被全球公司使用。所获得的数据将用于开发氨喷雾破碎，混合和燃烧后的排放物形成的模型。这一切都将与实验项目同时进行，并将确保项目的效用远远超出项目本身，开发的模型可供全球任何软件用户使用。

Ammonia (NH3) is a promising zero-carbon fuel for future transportation. Today transportation emits around 8.9 billion tonnes of CO2 annually. Whilst some sectors (e.g. cars) can be decarbonised using batteries, heavier transport (marine or freight) are less likely to use batteries due to their cost and energy density.Ammonia is a hydrogen carrier, and (by volume) contains 50% more hydrogen than liquid hydrogen (which alone is extremely energy intensive to liquefy and store). Ammonia has among the highest energy densities of any non-hydrocarbon (traditionally fossil) fuel. Ammonia is particularly attractive because it can be made using the well-established Haber-Bosch process, which today is used to make 230 million tonnes of ammonia per year. Ammonia production can be 100% renewable when powered by solar and wind. This means that ammonia production can be scalable and can be undertaken repurposing a large amount of existing infrastructure.A number of pilot projects are underway worldwide with Ammonia, including for energy storage, shipping and freight transportation. Many of these are in the UK, including at the Rutherford Appleton Laboratory, Cardiff University and the University of Nottingham. However, these projects typically adapt existing technology, which is designed for a different fuel (fossil fuels usually). There is a significant lack of fundamental data to enable the design of energy conversion systems specific to ammonia. This project, AmmoSpray, aims to fill this gap. AmmoSpray will provide, for the first time, fundamental data on ammonia sprays into air. Ammonia can be sprayed into air either as a liquid or as a gas, and both will be investigated in this project. The fundamental data obtained will include spray break-up (how liquid ammonia breaks up and evaporates upon injection) and how ammonia and air mix under realistic conditions. These studies will be undertaken on three different pieces of test equipment:1. An ambient conditions spray rig2. A Cold Driven Shock Tube (CDST)3. An optical access thermal propulsion system (TPS)The spray rig is fast and cheap to run, and will enable the development of the experimental systems required for this project, the testing of large numbers of spray test conditions, and will be used to undertake a scoping exercise to identify project boundaries.The CDST is a unique facility in the UK, able to replicate conditions found during combustion (150 bar pressure, 1500 K temperature) without turbulence, and with space for test equipment. This will enable for the first time imaging and break-up studies of ammonia sprays at conditions that will be seen in-use - key fundamental data.The optical TPS tests are the logical next step, adding turbulence, and replicating as closely as possible 'real' conditions, whilst still allowing access for imaging and test equipment. The key tests here will be on mixing, using a laser-based technique (PLIF) to obtain ammonia:air ratio measurements throughout the combustion volume. This will link the sprays information developed earlier to their combustion characteristics. The tests on the optical access TPS will also enable studies of how these different spray and mixing methodologies influence emissions formation for ammonia combustion, with NH3 and NOx the key emissions which will be measured. This step-by-step nature is perfectly suited for improving existing models. The data obtained will be coded into commercial modelling software (computational fluid dynamics (CFD)) provided by project partner, Convergent Science. Its CONVERGE CFD software is used by companies globally. The data obtained will be used to develop models for ammonia spray break-up, mixing, and emissions formation upon combustion. This will all happen in parallel with the experimental program and will ensure that the project's utility well beyond the project itself, with the models developed being available to be used by any of the global users of the software.