Boundary layer separation for mechanical seal applications-

Boundary layer separation for mechanical seal applications

　2017-03-04　　

Boundary layer separation for mechanical seal applications

The phenomenon that the boundary layer of mechanical seal separates from the wall surface, and the phenomenon of backflow and large vortex at the same time is called boundary layer separation.

Reasons for separation:

In the quiet situation where the external potential flow is constantly pressurizing along the flow direction, the function of the fluid particles in the boundary layer is consumed by overcoming viscous force on the one hand and continuously converted into pressure energy on the other hand. Therefore, the function of each particle becomes smaller and smaller along the process. Until a certain point, the kinetic energy of the fluid particle closest to the wall drops to zero and stagnates. After this point, the fluid particles that are far away from the wall are forced to flow backwards under the action of the pressure difference opposite to the flow direction. However, the fluid particles in the boundary layer farther from the wall still have a certain amount of kinetic energy and continue to move forward. Due to this opposite flow action, backflow and large vortices are formed, and the boundary layer is forced to squeeze away from the wall and separate.　　325.html,

The transition of the boundary layer of the mechanical seal application 　　 the result of the boundary layer separation of the mechanical seal