In this paper, the 3 D velocity fields in the furnaces' arch area for a conventional stock boiler and the model with dipole vortex device were measured by the hot wire aerometer.

When the inclination angle of a side nozzle is 0, 30,45 and 60 degrees, the eddying flow of the bottom hole vortex device will cause rotation at the bottom hole, affecting on the jet from bit nozzles.

In the middle pressure chamber upside sets floating seal device, so vortex top and middle pressure by exhaust pressure role.