Low NOx Combustion System
Requirements for stationary gas turbines with regard to their competitiveness in the power plant market are changing. As a result of the expansion of renewable energies with a volatile availability compared to full-load operation, part-load operation is gaining importance. At the same time, legal requirements on emission limits are steadily becoming more stringent. These requirements are passed on to the manufacturer in form of warranty claims. In order to be able to meet these emission limits over the entire service life, aging effects must be taken into account.
Due to the formation mechanisms of pollutants, the emissions of a gas turbine are dependent on the air distribution in the combustion system, which is generally optimized for nominal load operation; the emissions may vary by several orders of magnitude, depending on species and operating conditions, due to incomplete mixing and local extinction. During operation, aging phenomena have a long-term impact on the combustion system, since the air distribution in the combustion chamber changes continuously as a result of erosion of material as well as cross-section obstructions. So far, few findings, which are necessary to apply adaptations to components and operating modes during the aging process are available
From an economic point of view, aging phenomena on compressors and turbines are of interest, which alter the overall performance and the overall efficiency of the gas turbine and thus have an influence on overall operating costs.
Within the scope of this project, a gas turbine model is to be developed, which is able to reflect the temporal changes in emissions and component behavior. Within the framework of a statistical analysis of power plant data over several years of operation, the relevant influencing variables on the aging effects are to be identified and combined in an aging model. This statistical model provides the boundary conditions for a chemical modeling of the combustion chamber to determine emissions. The goal is a model for predicting the component aging and the emission levels as a function of the operating time.
The project is realized as part of the AG Turbo joint project "AG Turbo 2020" and funded by the Federal Ministry for Economic Affairs and Energy (BMWi) in a period of 3 years.
Christian Rudolf, Manfred Wirsum, Martin Gassner, Stefano Bernero Analysis of Long-Term Gas Turbine Operation With a Model-Based Data Reconciliation Technique ,ASME Turbo Expo 2015, GT2015-42497, Montreal, Quebec, Canada, June 15–19, 2015