Ön karışımsız swirl brülör simulasyonu.

Flame stabilizing in a gas turbine combustion chamber is one of the designing issues. Non-premixed swirling flames are commonly applied to aerial vehicles’ combustors due to their advantages in flame stabilizing and flame length shortening. However, swirling flows are very complex and hard to simulate even without reaction. Previous studies have showed that Large Eddy Simulation (LES) is able to predict swirling flow with a good degree of accuracy. On the other, it is quite expensive and is still far away for being a routine approach as a design tool in industry. Unsteady Reynolds Averaged Navier Stokes (URANS) approach alters LES for being cheaper and reasonably accurate. This study aims to simulate a nonpremixed highly swirling flame. TECFLAM S09 methane-air flame case with 0.9 swirling number and 150kW thermal power is selected which is a good candidate for investigating such flows. Realizable k-epsilon turbulence model is used with various combustion models. Mesh study is performed up to 38 million hexahedral elements. Results of URANS solutions are compared with LES. It is seen that flow field calculation is highly dependent on combustion phenomenon. But, LES predicts far better accurate solutions than URANS. On the other hand, LES is at least 10 times more expensive than URANS and turbulence models other than Realizable k-epsilon should be investigated to totally eliminate URANS for a highly swirling reactive flow.M.S. - Master of Scienc