Fluid circulation apparatus using fluid flow deflection grating

A low head loss fluid circulation apparatus, said apparatus comprising:

• duct means defining a circulation fluid flow path,
• a drying chamber or the like within said flow path formed by an upstream inlet grating spanning said flow path and spaced from a downstream outlet grating which also spans said flow path and with said gratings extending generally parallel to each other and perpendicular to the flow path,
• and wherein said flow path duct means include at least an oblique flow path portion upstream of said inlet grating and leading thereto,
• and wherein said inlet grating comprises a fluid flow deflection grating for receiving an incident flow of fluid arriving along an incident direction defined by said first oblique flow path portion and for forming an exit flow of fluid leaving along an exit direction that is at least 45.degree. different from the incident direction,
• and wherein the fluid flow is substantially uniform over its entire cross-section at a distance from the grating,
• said inlet fluid flow deflection grating being in the shape of a panel constituted by at least one thin, corrugated, perforated sheet, each corrugation being in the form of at least two substantially plane flank strips, said plane flank strips and said corrugations formed thereby extending lengthwise in a direction perpendicular to both the fluid flow incident and exit directions, said plane flank strips being spaced from each other and being joined by a bottom strip to define with said plane flank strips a valley opening to the fluid flow incident direction, at least some of the perforations in said sheet being through said bottom strips, and wherein said perforations extend over at least fifty percent of the surface area of said bottom strips.