Investigation on Vortex Characteristics of a Multi-Blade Centrifugal Fan near Volute Outlet Region

Abstract

The origins and effects of the complex vortex structure near the volute outlet of a multi-blade centrifugal fan are investigated in this paper. Due to the wide blade and short blade channel, the airflow maintains a large radial velocity during the blade channel. This continuous radial partial velocity causes vortices to be generated at the region of volute outlet. Then, the secondary flow close to the impeller generate from the center to the sides in volute. It is obtained that the streamlines are divided into two parts (backflow and outflow) at volute outlet. Although the vortices near volute outlet region are complex, the main features of flow behavior caused by the vortex are understandable.

Aerodynamics Optimization of Multi-Blade Centrifugal Fan Based on Extreme Learning Machine Surrogate Model and Particle Swarm Optimization Algorithm

“…Xu et al [1] Groove width, groove depth, groove center distance, groove number, different groove shapes CFD simulation design method Ye et al [2] Inner diameter, bevel-cutting blade CFD technology, test Li et al [3] Vortex characteristics CFD technology Wei et al [4] Clearance, the inclination angle, the volute tongue CFD technology, test Zhou et al [5][6][7] Multi-blade centrifugal fan blade airfoil parameter The scroll cut-off angle, the scroll diffuser expansion angle, the diameter ratio of the impeller, the blade exit angle The main research methods for rotating machinery are based on CFD and the surrogate model. For example, among the above literature about multi-blade centrifugal fans, references [1][2][3]11] are based on CFD research and references [5][6][7]12] are based on CFD and surrogate model research.…”

“…Ye et al [2] improved the multi-blade centrifugal fan performance by changing inlet structure parameters based on a bevel-cutting design method and computer simulation technology. Li et al [3] studied the vortex characteristics of a multi-blade centrifugal fan near the volute outlet region. Wei et al [4] researched the effect of clearance, the inclination angle, and the volute tongue on a multi-blade centrifugal fan's aerodynamic performance.…”

Internal Flow and Aerodynamic Optimization of a Multi-Blade Centrifugal Fan

“…Because the left and right structure of the fan is symmetrical, and referring to the simulation results of similar fans [10], the internal flow field of this type of fan is symmetrically distributed. Therefore, during the calculation, only half of the internal watershed is divided along the symmetry plane, and the boundary conditions are set as symmetry in the software.…”

Volute Optimization Based on Self-Adaption Kriging Surrogate Model

“…Huang and Tseng [14] used the Levenberg-Marquardt method and inverse design technology in determining the optimal shape of the volute spiral case for a centrifugal fan. Li et al [15] researched the vortex characteristics of a centrifugal fan near the volute outlet region. Based on the optimization of volute profle, the orthogonal experimental design method is adopted to couple the three factors of volute width, volute tongue clearance, and relative axial position of the impeller, and the experimental scheme is determined through the orthogonal table.…”