Patent ID: 7587951
Filing Date: 2009-09-15
Classification: G01N,Y10T

Abstract:
1. A thermophoresis-resistant gas dilution apparatus, comprising: a housing having a first end and a second end and defining an interior space, the second end including an exit port in communication with the interior space through which gas exits the apparatus; a wall disposed within the interior space of the housing and dividing the interior space into an inner flow path defined by the wall and an outer flow path defined between the housing and the wall, the inner flow path being in communication with the exit port; a gas stream inlet adjacent the first end of the housing, the gas stream inlet opening into the inner flow path to permit introduction of a gas stream into the inner flow path; a dilution gas inlet in the housing adjacent the second end thereof, the dilution gas inlet opening into the outer flow path to permit introduction of dilution gas into the outer flow path, the dilution gas inlet comprises a plurality of inlet ports that are radial relative to a longitudinal axis of the housing; and a plurality of holes in the wall axially spaced from the dilution gas inlet that place the outer flow path in communication with the inner flow path; the apparatus is configured and arranged so that dilution gas introduced into the outer flow path is in heat exchange relationship with gas in the inner flow path over a substantial distance between the first end and the second end prior to the dilution gas in the outer flow path being introduced into the inner flow path.