Turbulent combustion modelling for conditions relevant to industrial applications

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Increasingly stringent regulations on airborne pollutant emissions for transportation and power generation are being imposed worldwide. Uncertainties in oil prices have further accelerated the search for alternative fuel-efficient and low-emission power generation systems. Experimental studies play an important role in the investigation of the issues arising in industrial combustion chambers; however, comprehensive experiments cannot be run routinely due to cost and large turnaround times. Thus, there is a clear need to develop computational tools capable of predicting transient phenomena, specifically ignition and extinction, as well as temperatures and emission levels for various fuels for design and optimization of industrial burners and engines. This proposal outlines a research program with the long-term objective of developing an efficient and accurate computational methods and models for the prediction of flame characteristics and pollutant emissions in the diverse combustion operating conditions relevant to those found in the power generation and transport industry. The two short-term objectives of the proposed program focus on two key aspects that require different physical modelling considerations: i. Accurate prediction of transient phenomena such as extinction and ignition for selected cases in conditions relevant to industrial applications.ii. Accurate simulation of combustion processes burning complex fuel blends using detailed chemistry with emphasis on atmospheric pollutant predictions. The proposed research program builds upon our recently developed Conditional Source-term Estimation (CSE) methods to bring them to a much higher level of development and improved confidence for the prediction of ignition/extinction and atmospheric emissions from complex fuels, in industrial applications. Experimental data sets from situations with increasing physical complexity will be selected to cover different conditions and phenomena that are found in industrial combustion chambers and engines. These cases present data with which to assess the prediction of ignition/extinction and generate maps for combustion stability, as well as the accuracy of the combustion process for complex fuel blends. Accurate, next-generation chemistry tables will be elaborated that include differential diffusion. Most simulations will be run in Large Eddy Simulation (LES) with a few developments using a Reynolds Averaged Navier Stokes (RANS) approach.The tools will be designed to be versatile and automated, requiring minimal user input. The techniques to be developed are of direct relevance to the engineering and research community as they will facilitate improved and efficient prediction and investigation of flame stabilization, ignition/extinction and emissions in industrial systems such as gas turbines, furnaces and boilers.