PRESSURE REDUCTION DEVICE FOR PARTICLE SAMPLING FROM COMPRESSED GASES

摘要

Disclosed is a device for particle sampling from compressed gases. The device allows for analyzing particles from compressed gases of a pressure ranging from 20 psi to 3000 psi. In the device, the formula Ds = Dt ? (Qs/Qt) is applicable wherein Ds and Dt are the probe diameter and the chamber diameter, respectively, Qs is the sampling flow rate required by monitoring instruments, and Qt is the total flow rate determined by the orifice diameter and pressure whereby the sampling velocity substantially matches the local flow velocity at the probe. In addition, a distance between the orifice and the probe is greater than L wherein L = Dc/ (2 tan .alpha. ) where Dc is the chamber diameter and a is the half angle of jet expansion.