Vortical structures from controlled circular jet

원형제트의 제어를 통한 보텍스 구조

The objective of this work is to study various vortical structures from controlled circular jet such as trifurcating and blooming jets. The numerical simulations of flow from a circular jet are carried out at $Re_D=4300$ based on the jet-exit velocity and jet diameter using large eddy simulation with the dynamic Smagorinsky model in a cylindrical coordinate system. The excitation for the controlled jet is achieved by combining axial and helical excitations. The axial velocity controlled by blowing and suction at the jet exit has several peaks in their cycle with respect to ratio of axial to helical excitations. This active control changes the spreading angle and vortical structures in the downstream region.