Air-resistance type sealing structure and working method

The invention discloses an air-resistance type sealing structure and a working method. The air-resistance type sealing structure is structured such that a high pressure drainage pipe is additionally arranged on the wall surface of an upstream end of an air flow of a conventional labyrinth seal stationary sub block, part of high pressure air flow is introduced into a pressure equalizing slow flow chamber in the stationary sub block through the drainage pipe, and the air flow is pressed in uniformly further through a pressure inflating air guide pipe in an inner cavity. By means of an air flow pressure inflating method, the effective pressure difference in a front seal area is reduced, so that the original power leaked from a gap is reduced from the origin. Meanwhile, under induction of highpressure jet entrainment, a large-dimension vortex structure which fills the whole chamber is further formed in a middle cavity of the seal gap connected to the pressure inflating air guide pipe in the inner cavity, so that the energy dissipation is enhanced, the leakage amount of the gap is reduced and the safety and economic benefit of operation of a unit are improved.