Like to car manufacturers, aircraft manufacturers are faced with the need to develop low emission gas turbine technology, especially technology to reduce NOx emissions. There is much synergy between internal combustion engines and gas turbines which enters into this research.
The project will develop and validate a computer simulation model for use in the design of high pressure industrial combustion chambers. The code will be the subject of experimental new designs for industrial gas turbines. NOx abatement strategies will be explored and an optimum design will be proposed.
This project achieved the majority of its aims. A description of a detailed kinetics mechanism to model NOx formulation at various pressures has been achieved and a detailed mechanism reduction has been obtained. Further work, however, is currently being conducted on the TECK model, which is not yet completely formulated. The model describes the turbulent microstructure with mean flow properties and the effect of thermal radiation is not taken into account.
The project involves two research organizations specialized in combustion modelling (BERTIN, UKAEA Harwell) and a major European manufacturer of industrial gas turbines (EGT). The basic idea is to use 3D modelling of existing gas turbines with a appropriate description of turbulent combustion and NOx chemistry, in order to identify NOx abatement strategies and to derive new efficient designs. The specific advantage of numerical simulation is to provide detailed insight and understanding of combustion/pollution processes, whereas experimental detailed measurements prove difficult and costly.
The key technical issues of the project are the following:
- Development of a turbulent combustion model capable of handling those features that are required for NOx description (BERTIN):local temperature levels and fluctuations, minor species concentrations, multi-step chemistry; this model will be implemented in three commercially available CFD softwares (one in each partner laboratory), so that each partner makes most efficient use of the model in conjunction with its own expertise.
- Detailed description of NOx formation and destruction mechanisms, in conditions relevant to gas turbine operation (UKAEA Harwell); this will include an extensive state of the art compilation of chemical data, and a mathematical treatment to come up with reduced schemes tractable by the 3D CFD codes; this work will make use of the most recent advances carried out by the project partners in the field of chemical kinetics.
- Investigations of NOx mechanisms within industrial gas turbine combustors (EGT): numerical simulations of existing combustors, combined with available experimental data, are expected to provide a deep insight on pollutant formation processes and their interactions with combustion based on this knowledge, new designs will be tested in order to achieve both combustion efficiency and low pollutant emissions.
Funding SchemeCSC - Cost-sharing contracts
OX11 0RA Didcot - Oxfordshire