DMD Modal Analysis of Film-Cooling Flow

Detection and analysis of various flow structures is one of the challenges in studying complex flows. Dynamic Mode Decomposition (DMD) is a mathematical technique used to identify the dominant physical modes of fluid flow. In DMD Method, Identification of the most dominant Modes to predict the Future dynamics of the Flow Field is a significant challenge. A numerical solution has been performed for the DMD analysis using the LES method. The thermal field and flow velocity of the Film-cooling have been studied and compared with Experimental Data. The results of the numerical solution have been subjected to modal analysis in the form of data. The results show that dominant modes for temperature are completely different from the dominant modes for velocity. It shows that the changes of velocity and temperature vectors are not coupled and synchronous. The dominant modes for temperature have low frequencies, which are mostly due to CVP physics. The dominant modes for velocity have high frequencies, which are due to K-H. The high-frequency modes for temperature have a negligible effect on the wall temperature and are mainly effective in the region near the Duct. Three Most important Modes of temperature Field have frequencies of ۵۹۶, ۴۶۲ and ۳۰۱, respectively. These low-frequency structures are caused by CRVP structures that affect the cooling field at high blowdown ratios.

Keywords:

LES , Film-cooling , Modal Analysis , Dynamic Mode Decomposition , Dominant Mode