Patent Document ID: 20030230489
Application ID: 10456772
Patent Flag: 0

Claim One:
1. A flow channel, comprising: a plurality of connected channel regions, each of said channel regions comprising a longitudinal axis, a top surface substantially parallel to a bottom surface, and first and second side walls each aligned substantially parallel to said longitudinal axis; adjacent first and second channel regions intersecting at a first intersection plane, wherein said first and second side walls of said respective first and second channel regions meet at said first intersection plane, and wherein a normal to said first intersection plane is oriented at an angle, &thgr; 11, with respect to said longitudinal axis of said first channel region, and oriented at an angle, &thgr; 12, with respect to the longitudinal axis of said second channel region; and means for establishing a first channel permeability, &sgr; a1, in said first channel region, wherein 0.75&sgr; 1 <&sgr; a1 <1.25&sgr; 1, and means for establishing a second channel permeability, &sgr; a2, in said second channel region, wherein 0.75&sgr; 2 <&sgr; a2 <1.25&sgr; 2, where &sgr; 1 and &sgr; 2 are first and second predetermined design permeabilities related by a compatibility condition comprising 12 tan &it; &it; θ 11 σ 1 = tan &it; &it; θ 12 σ 2, wherein a fluid flowing from said first channel region into said second channel region and comprising a flux that is substantially uniform in said first channel region remains substantially uniform in said second channel region.