Technology Development for Next Generation of Gas Turbine Engines: Turbulent Combustion Science and Thermoacoustics

2016年，飞机和发电行业为加拿大政府贡献了约700亿加元的收入。今天，这些行业在使用燃气轮机发动机方面面临两个主要挑战。首先，它们使用的化石燃料是有限的自然资源，需要由未来的替代燃料(例如非食用生物质)取代。目前与燃气轮机发动机条件相关的化石燃料和替代燃料燃速的相关知识有限，这种局限性阻碍了我们开发下一代燃气轮机发动机的能力。需要开发知识和技术来估计和提高燃气轮机发动机中化石燃料和未来替代燃料的燃速。这些行业面临的第二个挑战是污染物的排放，例如氮氧化物和颗粒物。这些因素在一定程度上导致了2016年约7.22亿吨的温室气体排放；通过国际协议，加拿大承诺在30年内将这一排放量减少约80%。今天，通过使用燃油喷射技术，可以在燃烧前增强燃料和空气的预混合，从而减少氮氧化物和颗粒物的排放。然而，预混火焰容易发生热声振荡(这不利于发动机的运行)，需要开发能够缓解这些振荡的技术。*拟议的研究计划将在两个平行的方面进行：(I)提高预混火焰的燃烧速度(对于气体和液体化石/替代燃料)，以及(Ii)缓解热声振荡。对于气态燃料，将首先研究强烈湍流和预混火焰相互作用的动力学(这与发动机应用有关)。然后，所产生的知识将被用于开发一种允许提高气体燃料燃烧速度的新型流动控制装置。该装置将与稀薄预混和预混装置集成，以研究化石和替代液体燃料的燃速。将开发相应燃速的模型，并将其转移到相关行业。在第二方面，我们将首先研究喷雾火焰中热声振荡的动力学。然后，这项研究将通过开发一种允许缓解热声振荡的新型燃油喷射技术来补充。*拟议的计划将产生开发未来燃气轮机所需的知识和技术，这些涡轮机具有更高的燃料燃烧速度，减少温室气体排放，并改善发动机寿命。这将节省加拿大的自然资源，帮助加拿大政府遵守与污染物排放有关的国际协议，减缓全球变暖，并提高飞机发动机的安全性。

Aircraft and electric power generation industries contributed to about $70B CAD revenue for the government of Canada in 2016. Today, these industries face two main challenges relating to their use of gas turbine engines. First, they operate with fossil fuels which are limited natural resources and need to be replaced by future alternative fuels (e.g. non-edible biomass). Current knowledge related to both fossil and alternative fuels burning rates relevant to gas turbine engine conditions is limited, and this limitation has hindered our capability of developing the next generation of gas turbine engines. Both knowledge and technology need to be developed to estimate and enhance the burning rate of fossil and future alternative fuels in gas turbine engines.******The second challenge these industries face is the emission of pollutants, e.g. nitrogen oxides and particulate matter. These partly contributed to about 722 mega tonnes of greenhouse gas emission in 2016; and, through international agreements, Canada has committed to reduce this emission by about 80% in thirty years. Today, reducing emissions of nitrogen oxides and particulate matter has been made possible by utilizing fuel injection technology that allows for enhanced fuel and air premixing prior to combustion. However, premixed flames are prone to thermoacoustic oscillations (which are detrimental to engine operation) and technology that allows for mitigation of these oscillations needs to be developed.******The proposed research program will pursue two parallel fronts: (I) enhancing burning rate of premixed flames (for both gaseous as well as liquid fossil/alternative fuels), and (II) mitigating thermoacoustic oscillations. For gaseous fuels, dynamics of intense turbulent flow and premixed flames interaction (which is relevant to engine applications) will be first investigated. The generated knowledge will then be used to develop a novel flow control apparatus that allows for enhanced gaseous fuel burning rate. This apparatus will be integrated with a lean premixing and prevaporizing unit to study burning rate of both fossil and alternative liquid fuels. Models for the corresponding burning rate will be developed and transferred to the relevant industry. On the second front, dynamics of thermoacoustic oscillations in spray flames will be first investigated. Then, this study will be complemented by development of a novel fuel injection technology that allows for mitigation of thermoacoustic oscillations.******The proposed program will generate knowledge and technology required for development of future gas turbines that feature enhanced fuel burning rate, reduced greenhouse gas emission, and improved engine life-time. These will save Canadian natural resources, help the government of Canada comply with its international agreements related to pollutants emission, decelerate global warming, and enhance aircraft engines safety.