The present paper reports on the numerical simulation of flow dynamics in a model gas-turbine combustor by large eddy simulation in order to evaluate the effect of coherent flow structures on the local fluctuations of gas temperature and local concentrations of NO and CO. The simulations were performed for a generic swirler, based on the design by Turbomeca, for a Reynolds number of 15,000 at normal and elevated inlet temperature and pressure (up to 500 K and 3.4 atm). The simulation data were validated based on the velocity measurements by stereoscopic particle image velocimetry. In order to reveal coherent flow structures, the velocity snapshots were processed by the proper orthogonal method. The temporal coefficients of the decomposition were used to evaluate the conditional sampled spatial distributions of the temperature and species concentration. It is shown that the coherent fluctuations of temperature can locally reach up to 200 K with the fluctuations of NO up to 20%. Thus, the results demonstrate that coherent flow structures in a lean swirl combustor can sufficiently contribute to NOx emission.
Предметные области OECD FOS+WOS
- 2.07 ЭНЕРГЕТИКА И РАЦИОНАЛЬНОЕ ПРИРОДОПОЛЬЗОВАНИЕ
- 1.07 ПРОЧИЕ ЕСТЕСТВЕННЫЕ И ТОЧНЫЕ НАУКИ
- 2.02 ЭЛЕКТРОТЕХНИКА, ЭЛЕКТРОННАЯ ТЕХНИКА, ИНФОРМАЦИОННЫЕ ТЕХНОЛОГИИ