Patent ID: 8707676

Claim:
A fuel grain for providing an exhaust, comprising: a solid fuel body; a solid fuel core; an entry having an entry gas flow; an exit having an exit gas flow for passing a gas flow through the fuel grain between the entry and the exit; at least two axial channels disposed between the entry and exit, the solid fuel body and solid fuel core at least partially defining the at least two axial channels, and only one of the at least two axial channels being in axial alignment with at least one of the entry and the exit; and at least one radial channel disposed between the entry and exit, and the at least one radial channel extending radially between two of the at least two axial channels and extending axially through only a portion of a longitudinal axis of the fuel grain, the solid fuel body and solid fuel core at least partially defining the at least one radial channel wherein at least one of the at least one radial channel is a buried channel comprising a first end for receiving the gas flow and a second distal end for expelling the gas flow, wherein only the second end of the buried radial channel is in fluid communication with the first of the at least two axial channels to limit an initial gas flow in the fuel grain.