How to Optimise the Outlet Design of Fan Volutes for Industrial Boilers

How to Optimise the Outlet Design of Fan Volutes for Industrial Boilers

Based on air performance measurements of industrial boiler fans, and in strict accordance with performance testing of standardised air ducts for such fans, this study illustrates examples of predicting particle trajectories in accordance with the requirements of noise measurement methods for industrial boiler fans. Through technical numerical simulation, the gas-solid two-phase flow in the flow field of industrial boiler fans was calculated, and numerical calculations were performed on the three-dimensional unsteady flow upstream of the centrifugal fan, identifying three structural parameters related to vortex shedding. Numerical calculations and experimental results indicate that optimisation can effectively reduce the impact of impeller clearance on the efficiency and noise of industrial boiler fans, whilst maintaining essentially unchanged efficiency, thereby yielding reliable mechanical digital responses and technical insights. The surface method can be employed to guide the improvement and experimental planning of centrifugal fans. Compression algorithms are used to conduct three-dimensional simulations and tests of industrial boiler fan performance. Under the fan’s design conditions, the velocity and pressure distributions within the propeller and convoluted flow channels were analysed. Compared with experimental data, the numerical simulation results were more accurate in terms of performance parameters, and the improved vortex profile resolved the flow issues. According to the numerical analysis, the flow field within the propeller was significantly improved beyond the vortex deformation line. The fan’s aerodynamic performance and noise characteristics, as well as their impact on the installation site, were investigated. To reduce noise in industrial boiler fans, the inclination angle and installation distance of the spiral vanes have a specific interaction with the fan’s aerodynamic performance. To accurately and visually represent the dust passage of various particle sizes within industrial boiler fans, a range of inclination angles and installation distances were selected. On this basis, the influence of particle size on particle trajectories was analysed, providing a foundation for research into blade wear in industrial boiler fans. As one of the key working components of a combined cleaning system, industrial boiler fans have a significant impact on the cleaning performance of harvesters.