Patent attributes
The use of externally-pressurized porous media in shaft sealing for turbomachinery is provided for single seals, tandem seals, double-opposed seals, and a ventless seal. These arrangements provide for significant benefits, such as the following: (a) external pressurization allows frozen seal faces to lift open before rotation, (b) pressure is distributed uniformly across the seal face, as opposed to allowing leakage to pass over it, (c) low flow rates of injected gas are possible, (d) the seal faces are self-defending due to the uniform pressure in the gap, and (e) complete elimination of venting process gas is possible. By employing externally-pressurized porous media sealing, a drastic simplification of seal design, as well as gas treatment and seal panel design, is possible.