Patent ID: 8307943

Claim:
A device for reducing pressure of a fluid comprising: an inlet flow conduit that channels a flow having an inlet pressure into a plenum, wherein the inlet flow conduit and the plenum are configured to induce a turning and swirling motion in the flow; an orifice plate stack comprising a plurality of orifice plates coupled to the plenum such that the flow from the plenum flows through a plurality of orifices in the orifice plates into an inner cavity, each orifice plate having a plurality of orifices such that pressure of the flow from the plenum to the inner cavity is reduced as it flows through the orifice plate stack; and a flow straightener layer coupled to the inner cavity such that the flow from the inner cavity exits through the flow straightener layer such that the device reduces the pressure of the fluid from the inlet pressure to an exit pressure; wherein a first orifice plate in the orifice plate stack has a first orifice having a first size, a second orifice plate has a second orifice having a second size, and a third orifice plate has a third orifice having a third size; wherein the first orifice plate and the second orifice plate are oriented relative to each other such that a flow through the first orifice impinges on a wall portion of the second orifice plate; wherein a flow area of the first orifice plate and a flow area of the second orifice plate are substantially the same; wherein the third orifice plate has a flow area that is substantially greater than the flow area of the first orifice plate and the flow area of the second orifice plate; and wherein the flow causes a choked condition at the second orifice plate and an unchoked condition at the first orifice plate and the third orifice plate.