Abstract: Particular embodiments of the inventive technology present a method for optimizing fan performance by, e.g., adjusting fan efficiency and/or acoustics to match, or more closely match, system design requirements or preferences. Embodiments may involve the selection of a size of centrifugal fan 18 from the plurality that can fit inside a certain housing, forming a fan unit that provides an annular output 19; such selection may be made to achieve certain performance goals. Add-on appurtenances such as one or more of, e.g., an annular housing extension 10, fixed vanes 12, and acoustic treatment 8, may be used to tailor the fan unit to meet system requirements, e.g., regarding efficiency, acoustic/sonic performance (e.g., noise generated by the fan), and/or static efficiency.

Abstract: Embodiments of the inventive technology may include an automatically reconfigurable flow blocking damper to prevent back flow; applications include, e.g., centrifugal fans that may at times be susceptible to such back flow, such as centrifugal fans established in an array and discharging to a common space. A clutch may effect damper engagement with rotatable componentry such that the damper is engaged with rotatable componentry when the damper is in open configuration, and effect damper disengagement from rotatable componentry such that the damper is disengaged from rotatable componentry when the damper is in closed configuration. The clutch may, in particular embodiments, act to prevent rotational imbalance problems otherwise observed when the damper is engaged to and rotates with rotatable componentry.

Abstract: Particular embodiments of the inventive technology present a method for optimizing fan performance by, e.g., adjusting fan efficiency and/or acoustics to match, or more closely match, system design requirements or preferences. Embodiments may involve the selection of a size of centrifugal fan 18 from the plurality that can fit inside a certain housing, forming a fan unit that provides an annular output 19; such selection may be made to achieve certain performance goals. Add-on appurtenances such as one or more of, e.g., an annular housing extension 10, fixed vanes 12, and acoustic treatment 8, may be used to tailor the fan unit to meet system requirements, e.g., regarding efficiency, acoustic/sonic performance (e.g., noise generated by the fan), and/or static efficiency.

Abstract: Embodiments of the inventive technology may include an automatically reconfigurable flow blocking damper to prevent back flow; applications include, e.g., centrifugal fans that may at times be susceptible to such back flow, such as centrifugal fans established in an array and discharging to a common space. A clutch may effect damper engagement with rotatable componentry such that the damper is engaged with rotatable componentry when the damper is in open configuration, and effect damper disengagement from rotatable componentry such that the damper is disengaged from rotatable componentry when the damper is in closed configuration. The clutch may, in particular embodiments, act to prevent rotational imbalance problems otherwise observed when the damper is engaged to and rotates with rotatable componentry.

Abstract: At least one embodiment of the present inventive technology focuses on a vaneless diffuser adapted for establishment extra-radially of a centrifugal fan, wherein the diffuser may effect an optimal transformation of velocity pressure into static pressure of a fluid (e.g., air) impelled by a centrifugal fan by decreasing that fluid's tangential velocity as it travels through the diffuser, without causing recirculation of air output from the diffuser back into the diffuser. Such diffuser may effect such a decrease in tangential velocity by radially extending the interface through which impelled air is output from the diffuser to a downflow fluid handling environment such as, e.g., a scroll and/or a plenum. The diffuser may converge in a direction parallel with the axis of rotation of the centrifugal fan to avoid fluid recirculation and/or may incorporate acoustical material so as to reduce the amount of material necessary for effective noise reduction as compared with convention noise reduction methods.

Abstract: At least one embodiment of the present inventive technology focuses on a vaneless diffuser adapted for establishment extra-radially of a centrifugal fan, wherein the diffuser may effect an optimal transformation of velocity pressure into static pressure of a fluid (e.g., air) impelled by a centrifugal fan by decreasing that fluid's tangential velocity as it travels through the diffuser, without causing recirculation of air output from the diffuser back into the diffuser. Such diffuser may effect such a decrease in tangential velocity by radially extending the interface through which impelled air is output from the diffuser to a downflow fluid handling environment such as, e.g., a scroll and/or a plenum. The diffuser may converge in a direction parallel with the axis of rotation of the centrifugal fan to avoid fluid recirculation and/or may incorporate acoustical material so as to reduce the amount of material necessary for effective noise reduction as compared with convention noise reduction methods.