Differential Alpha Variable Area Metering

An annular fluid flow control or metering device comprises: first and second annular plates disposed in an annular flow path, the first annular plate and second annular plates being made of different first and second materials, the first annular plate having a lower first coefficient of thermal expansion than a second coefficient of thermal expansion of the second annular plate, the first annular plate abutting or in contact with the second annular plate, the first annular plate including at least one first metering aperture, and the second annular plate being more thermally responsive than the first annular plate wherein the second annular plate being configured to radially grow and shrink to at least partly obstruct the at least one first metering aperture for metering or controlling a flow of fluid through the at least one first metering aperture. 环形流体流量控制或计量装置包括：设置在环形流动路径中的第一环形板和第二环形板，第一环形板和第二环形板由不同的第一和第二材料制成，所述第一环形板的第一热膨胀系数低于所述第二环形板的第二热膨胀系数，第一环形板与第二环形板邻接或接触，所述第一环形板包括至少一个第一计量孔，并且所述第二环形板比所述第一环形板具有更强的热响应，其中