| 摘要 |
Systems and methods for measuring and controlling fluid flow comprises an orifice plate defining a variable opening, wherein the orifice plate includes an outer assembly comprising a central opening and an inner assembly extending through the central opening. Another embodiment comprises a plurality of blades disposed parallel to each other, wherein the blades are pivotable along its longitudinal axis and include at least one low-flow blade or partial blade and a plurality of high-flow blades The flow device regulates high and very low volumes of fluid with precision, inexpensively, with superior acoustics, reduced energy, a simpler design, and prevents building infiltration. The high turndown device permits use at lower velocities, thereby reducing noise generation and eliminating need for sound-attenuating liners. The high rangeability device combines several part numbers into fewer parts, thereby streamlining product portfolios. Cost benefits associated with the flow device allow equipment to be scaled back 100:1 rather than legacy 4:1, providing energy savings, fewer product variations, simple and more robust applications. The device meets new and old building fresh air, comfort and energy codes. The flow device can be engineered, selected, and sized without sophisticated software programs. |
