Flow Ducts and Flow Straighteners

    The flow ducts are fabricated from fiber reinforced plastic molded over precision tooling. Interior surfaces have glass smooth, white, vinyl-ester, gel-coat, while exterior surfaces are spray finished with a medium blue, polyester, gel-coat enamel.

    The system air from the blower is discharged through a wide-angle diffuser that has perpendicular lap flanges. Then face flanges are fastened with bolts. The wide-angle diffuser section expands with a total included angle of 12.3' in the horizontal plane and 1.4' in the vertical plane. The wide-angle diffuser helps in lowering the speed before the air enters through the flow straighteners. In the settling length, a precision, hexagonal cell, aluminum honeycomb section is placed. This is followed by a mesh of high porosity (60%) stainless steel screens. The screens are mounted and tensioned using a proprietary design. Extruded aluminum frames cover the entire settling length. The settling length is followed by the contraction section that is a single-piece mold. The cross section of the contraction section is symmetric throughout, has a 9:1 ratio, and has analytically developed contours. The contraction section leads to the test section through a transition plexiglas section. Flow from the test section continues into the diffuser section that has miter flanges. The primary diffuser section expands with a total included angle of 7'. High porosity perforated plates are fastened 14.81 in. from the diffuser entrance and at the diffuser exit. Any discontinuities in fit and alignment could lead to disturbances in flow. Hence, careful attention is paid injoining mating sections. Test Section

    The test section is integral to the water tunnel test section. The water tunnel test section is 48 in. long by 6 in. high by 6 in. wide in the interior. The total test section is a