Liquid Ammonia Direct Injection (LADI) fundamental physics and modelling of the aero-thermodynamic of transitional atomisation regime

液氨直喷 (LADI) 基础物理和过渡雾化状态的空气热力学建模

• 批准号: EP/X022811/1
• 负责人: Shijie Xu
• 金额: $ 26万
• 依托单位: University of Birmingham
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX022811%2F1
• 关键词: Liquid; Ammonia; Direct; Injection; LADI

This proposal develops the knowledge and technology for direct injection (DI) of liquid ammonia (LNH3), as green and carbon-free alternative liquid fuel for engine applications. This is a critical step toward the decarbonisation of heavy road transportation and the power production sector. According to the International Energy Association report, LNH3 is considered as "the low hanging fruit" carbon-free hydrogen alternative energy carrier for the following reasons [1]. (1) Mass production and shipping infrastructure of LNH3 is already widely available thanks to its widespread applications in the fertiliser industry; (2) Storage of LNH3, in large quantity, is significantly safer and more economical than hydrogen-compared to hydrogen or natural gas (LNG), ammonia is liquefied at room temperature at 9.90 atm (similar to propane, a fuel with widespread domestic applications); (3) With a very high hydrogen density of kg H2 per 100 litres (even higher than liquid hydrogen), LNH3 is a prime hydrogen carrier. The heating value of LNH3 is lower than fossil fuels, e.g., diesel and gasoline, hence, more fuel is required to produce the same power out. The evolution in DI technology has enabled advanced injection strategies, by which highly precise and modulated multiple injections over an extended period of time allows delivering more fuels while improving the mixture quality by enhancing the evaporation and mixing. Especial emphasis is made on the recent engines developed at MAN and Wärtsilä, companies that are currently commercialising ammonia reciprocating engines for marine applications [2]. Problem: In theory, pure LNH3 DI-engines, as a viable solution for full decarbonisation of power and road transportation sectors, is achievable. However, there are currently technological barriers that prevent the widespread use of LNH3 to completely replace fossil fuels with zero-carbon emission engines. This lays in the following facts: (1) the reactivity of ammonia/air mixtures is very low and quite incompatible with the engine operating conditions; (2) spray of LNH3 is different from fossil fuels and exhibits a highly non-linear and unsteady behaviour which trigger significant combustion instabilities and catastrophic engine failure.In this project, we focus on the second issue by investigating LNH3 sprays in DI-engine applications.

这项建议发展了液氨(LNH3)直接喷射(DI)的知识和技术，作为发动机应用的绿色无碳替代液体燃料。这是迈向重型公路运输和电力生产行业脱碳的关键一步。根据国际能源协会的报告，LNH3被认为是“低垂的果实”的无碳氢替代能源载体，原因如下[1]。(1)由于在化肥行业的广泛应用，LNH3的大规模生产和运输基础设施已经广泛使用；(2)LNH3的大量存储比氢气更安全、更经济-与氢或天然气(LNG)相比，氨在室温下在9.90大气压下液化(类似于丙烷，一种在国内应用广泛的燃料)；(3)由于LNH3的氢密度非常高，每100升(甚至高于液氢)，LNH3是一种主要的氢载体。LNH3的热值低于柴油和汽油等化石燃料，因此需要更多的燃料才能产生相同的功率输出。直喷技术的发展使先进的喷射策略成为可能，通过这种策略，高精度和可调的多次喷射在较长的时间内允许输送更多燃料，同时通过增强蒸发和混合来改善混合气质量。特别强调了由MAN和Wärtsilä开发的最新发动机，这两家公司目前正在商业化用于船舶应用的氨往复式发动机[2]。问题：理论上，纯LNH3直喷式发动机作为电力和道路运输行业全面脱碳的可行解决方案是可以实现的。然而，目前存在一些技术障碍，阻碍了广泛使用LNH3，以零碳排放发动机完全取代化石燃料。这是因为：(1)氨/空气混合物的反应性很低，与发动机的运行条件很不相容；(2)LNH3的喷雾不同于化石燃料，具有高度的非线性和不稳定行为，会引发严重的燃烧不稳定性和灾难性的发动机故障。在本项目中，我们通过研究LNH3喷雾在直喷式发动机中的应用来关注第二个问题。