Prediction of Noise Emission, Power Consumption and Airflow Performance using Multidimensional Fan Curves

F3 - Fan Design Methods

The airflow performance of a proposed fan-cooled product or air-moving system is typically assessed early in the design process using fan curves. The same degree of forward-looking certainty can be achieved using multi-dimensional fan curves that include noise emission and power consumption data. The airflow performance curve is simply the locus of pressure-flow states achievable under various loads for a given speed, and could be called the "iso-speed" curve. Likewise, the iso-acoustic curve documents the operating points achievable for a given noise emission, and the iso-power curve for a given power consumption.
As with airflow performance, these curves are determined a priori by measurement on existing fans or by aeroacoustic computation and adapted by fan similarity laws to homologous cases. A designer may then confidently compare options including air mover type, diameter, number of parallel air movers and series stages to simultaneously meet airflow performance, noise emission, and power consumption goals. This method may also be used to document the influence of non-optimal inflow conditions, which may also then be included in the predictions. The paper will include a description of the method as well as applications involving typical curves for common air movers and recent experiences with design optimizations.