Abstract: An apparatus is disclosed for reducing pressure and velocity of a particulate-laden, supersonic vent gas stream from a pressure vessel such as an autoclave. The apparatus includes a diverging duct in which the vent gas expands, and a perforated plate located inside the diverging duct. The perforated plate provides an area reduction that increases back pressure and forces an upstream normal shock in the diverging duct, thereby bringing about a desired reduction in pressure and velocity. The perforated plate is comprised of a material, such as a ceramic, that is resistant to erosion by the abrasive particulate entrained in the high velocity vent gas. The perforated plate has a central portion provided with holes and an imperforate peripheral portion which is resiliently received between connection flanges of the duct.

Abstract: An apparatus is disclosed for reducing pressure and velocity of a particulate-laden, supersonic vent gas stream from a pressure vessel such as an autoclave. The apparatus includes a diverging duct in which the vent gas expands, and a perforated plate located inside the diverging duct. The perforated plate provides an area reduction that increases back pressure and forces an upstream normal shock in the diverging duct, thereby bringing about a desired reduction in pressure and velocity. The perforated plate is comprised of a material, such as a ceramic, that is resistant to erosion by the abrasive particulate entrained in the high velocity vent gas. The perforated plate has a central portion provided with holes and an imperforate peripheral portion which is resiliently received between connection flanges of the duct.

Abstract: A spread spectrum radio frequency communication system includes a Forward Error Correction (FEC) algorithm to encode digital data to provide a plurality of symbol groups, the FEC algorithm using a Reed Solomon FEC code, an interleaving algorithm to map each one of the plurality of symbol groups into a corresponding one of a plurality of coherent subbands, and a Walsh encoder to encode each one of the plurality of symbol groups.