Flow control grid

1. A flow control system for changing the direction of a fluid flow and developing a uniform flow velocity within a conduit, the flow control system comprising:

a flow distribution array comprising a plurality of tubes extending across a width of the conduit and secured between first and second sides of the conduit;

a plurality of channel assemblies disposed adjacent to one another and arranged in a stepped configuration; each channel assembly for receiving a portion of the fluid flow including:

a flow straightening section including a plurality of flow plates positioned substantially parallel to one another and spaced apart from one another to define a plurality of flow paths between the spaced flow plates;

a flow turning section disposed upstream of the flow straightening section, the flow turning section including a turning vane for directing a respective portion of the fluid flow substantially to the plurality of flow paths defined by the flow plates of the respective flow straightening section, the turning vane having an arcuate segment that extends outwardly and upstream from the flow straightening section: and the flow distribution array disposed upstream of the channel assemblies.

2. The flow control system of claim 1 wherein the flow straightening section has a first height and the flow plates are spaced apart from one another by a first width, and the first height divided by the first width defines an aspect ratio, the aspect ratio having a magnitude of about 3 to about 4.5.

3. The flow control system of claim 1 wherein the flow turning section defines a second substantially flat section extending upstream from the arcuate segment.

4. The flow control system of claim 1 wherein the turning vane is curved to change the direction of a fluid flowing therethrough by about ninety degrees.

5. The flow control system of claim 1 wherein the plurality of the tubes of the flow distribution array comprise at least one cylindrical member extending across the conduit.

6. The flow control system of claim 1 wherein the flow straightening section has a first height and the flow plates are spaced apart from one another by a first width, and the first height divided by the first width defines a first ratio, the first ratio having a magnitude of about 3 to about 4.5.

7. The flow control system of claim 1 being disposed in a selective catalytic reduction reactor.

8. The flow control system of claim 1 wherein the flow straightening section has a first height and the flow plates are spaced apart from one another by a first width, and the first height divided by the first width defines an aspect ratio, the aspect ratio having a magnitude of about 2 to about 9.

9. The flow control system of claim 1 , further characterized in that an inlet duct is in fluid communication with a hood section; and

the plurality of channel assemblies extending across the hood section in a stepped configuration.

10. The flow control system of claims 1 wherein the turning vane includes a first substantially flat segment being disposed downstream of the arcuate segment and in the flow straightening section to define a flow path in the flow straightening section.

11. The flow control system of claim 1 , wherein the flow plates are disposed vertically.

12. The flow control system of claim 1 wherein the plurality of tubes of the flow distribution array comprises a plurality of tubes extending across the conduit in an incline formation.

13. The flow control system of claim 1 further comprising first and second flow distribution arrays, the second flow distribution array having a plurality of spaced members disposed downstream of the first flow distribution array.