Exploration of novel fuels for gas turbine applications

由于非石油燃料正成为燃气轮机运营商的必需品，第二代生物燃料正在开发中，需要在未来几年对其进行广泛使用的评估。燃气轮机燃烧室的燃烧非常复杂，有许多强耦合变量相互作用，在有限的空间内制备具有非常严格排放标准的燃料-空气混合物。因此，现有的设计工具设计燃烧器是非常具体的燃料使用的性质。与模拟相结合的分析关联是用于解释诸如燃料蒸发、混合和扩散、强湍流气动流动、高温对流和辐射流动以及具有高能量传递的强化学反应等现象的设计工具。因此，燃料特性是一个关键因素，考虑到在高温下输送到涡轮部分的额外能量，但具有明确的轮廓以防止叶片侵蚀。设计中最重要的挑战是预测与反应温度密切相关的极低排放。因此，当一种新燃料被用于燃气轮机燃烧室时，所有的设计工具都必须得到改进，以适应现有或新开发的燃气轮机燃烧室性能的变化。使用经过验证的燃烧模型，可以更好地预测生物燃料燃气涡轮发动机的性能和污染物排放。本研究项目的目标是研究新型燃气轮机燃料在非燃烧和燃烧系统中的特性，以解耦它们与更简单的几何形状的相互作用，以识别控制燃烧现象的潜在变量，并从实验或数值数据中开发有用的相关模型。对于非燃烧系统，将使用先进的激光技术对燃料喷雾进行表征，以研究燃料性质变化对液滴形成和最终尺寸分布的影响。对于燃烧系统，它们将从简单的层流和湍流开式燃烧器变化到复杂的旋流通用燃烧器，接近现实的工业燃烧器。该项目还将向生物燃料生产商提供反馈，以便根据最终用户定制产品。

Since non-petroleum fuels are becoming a necessity for gas turbine operators, 2nd generation biofuels are in development and need to be evaluated for wide spread use in the coming years. Combustion in gas turbine combustors is very complex with many strongly coupled variables interacting to prepare the fuel air mixture in limited space with very stringent emission standards. Hence existing design tools to devise a combustor are very specific to properties of fuels in use. Analytical correlations paired with simulations are the design tools used to account for phenomena such as fuel evaporation, mixing and diffusion, the strong turbulent aerodyna- mic flow, the high temperature convective and radiating flow, and the strong chemical reaction with high- energy delivery. Therefore, fuel properties are a critical factor to account for added energy to the flow delivered to the turbine section at high temperature but with a well-defined profile to prevent blade erosion. The most significant challenge in design is to predict for very low emissions that are strongly coupled to reacting tempe- rature. Therefore when a new fuel is used in a gas turbine combustor, all the design tools have to be enhanced to account for changing properties in existing or newly developed gas turbine combustor. The performance and pollutant emissions for biofuelled gas turbine engines can be predicted with better accuracy, using validated combustion models. The objective of this research project is to study the characteristics of novel gas turbine fuels in non-combusting and combusting systems to decouple their interaction with simpler geometries to identify the underlying variables controlling the combustion phenomena and to develop useful correlation models from the experimental or numerical data. For non-combusting systems, fuel sprays will be characteri- zed with advanced laser techniques to study the influence of changing fuel properties on droplet formation and the ultimate size distribution fed to the combustor. For the combustion systems, they will vary from simple laminar and turbulent open burners, to complex swirl generic combustors, approaching realistic industrial combustors. This project will also provide feedback to biofuel producers to tailor their products to end users.