Impeller Design of a Centrifugal Fan with Blade Optimization

Abstract

A method is presented for redesigning a centrifugal impeller and its inlet duct. The double-discharge volute casing is a structural constraint and is maintained for its shape. The redesign effort was geared towards meeting the design volute exit pressure while reducing the power required to operate the fan. Given the high performance of the baseline impeller, the redesign adopted a high-fidelity CFD-based computational approach capable of accounting for all aerodynamic losses. The present effort utilized a numerical optimization with experiential steering techniques to redesign the fan blades, inlet duct, and shroud of the impeller. The resulting flow path modifications not only met the pressure requirement, but also reduced the fan power by 8.8% over the baseline. A refined CFD assessment of the impeller/volute coupling and the gap between the stationary duct and the rotating shroud revealed a reduction in efficiency due to the volute and the gap. The calculations verified that the new impeller matches better with the original volute. Model-fan measured data was used to validate CFD predictions and impeller design goals. The CFD results further demonstrate a Reynolds-number effect between the model- and full-scale fans.

An investigation into fishing boat optimisation using a hybrid algorithm

“…This technique therefore enables the optimisation of complex geometries (Sun et al, 2010). It has also been widely used in different optimisation problems (Lee et al, 2011;Li et al, 2016;Sun et al, 2010).…”

A Novel Optimization Based Design Method for Centrifugal Fans

“…A typical example (among many others) is the work by Lee et al [7] who used CFD-based optimization to reduce the shaft power of a centrifugal fan by 9 %. While CFD-based optimization can yield a highly efficient design of a specific machine, it suffers from long computing times.…”

Effect of blade type on a 3D FC centrifugal fan

“…They reported that increase in the number of blade increases the flow coefficient and efficiency. Lee and coworkers in 2011 [Lee et al 2011] presented numerical CFD optimization with experiential steering technique to redesign the backward centrifugal fan profile, inlet duct and shroud of the impeller. The goal of optimization was to reduce power consumption while maintaining a specified output pressure at the lift-side volute exit.…”