Numerical study of flow pattern on a diamond wing-body equipped with LEX at low angles of attack

Abstract

In this research, the characteristics of the flow field around the diamond wing equipped with LEX have been studied using the CFD. Investigations carried out at low angles of attack have included 5, 10, and 15 degrees, and Re= 2.16×105 based on the model length. An investigation of the vortical flow of the diamond wing can help identify the flow field characteristics and the phenomenon of vortex breakdown. The results indicated the presence of the LEV, at the angle of attack of 5 degrees and for the cross-section close to the wing apex. The pressure coefficient showed that there are two low-pressure areas inside the vortex, which reveals a dual-vortex structure. Close to the center of the vortex, the amount of vorticity increased. Increasing the angle of attack has led to expand the vortex core, which has finally created the conditions for the existence of secondary and third vortices. The third vortex rotates opposite the direction of the secondary vortex and in the same direction as the LEV. This subject, observed rarely on delta wings, leads to increased circulation and stability of the diamond wing.