Flow Field Of Centrifugal Fan Research Articles

Fluid-solid coupling field analysis of centrifugal fan based on nonlinear dynamics

According to the characteristics of Fluid-solid coupling flow field of centrifugal fan, fan aerodynamic performance signal collecting experiment under different conditions are carried out on the centrifugal fan test bed. The relationship among airflow pressure pulsation, noise and vibration are studied by using nonlinear dynamics methods such as phase space reconstruction, correlation dimension, and complexity and so on, which lays the foundation for predicting the fan running status by monitoring the signal of airflow pressure pulsation and the noise. The result shows that the phase diagram of airflow pressure pulsation signal attractor is the most distinct and regular among the three signals. The scope of the phase diagram increases and becomes sparse and confusing with the decrease of the flow, which reflects that pressure pulsation amplitude becomes larger and the internal flow deteriorates gradually with the decrease of flow. The correlation dimensions are calculated with G-P algorithm of the three signals first decrease and then increase with the decrease of the flow. The correlation dimension of the airflow pressure pulsation or noise under stall operating condition can be used as monitoring indicators. The L-Z complexity of the noise increases constantly with the decrease of the flow. But the L-Z complexity of airflow pressure pulsation and vibration first decreases and then increases with the decrease of the flow.

Effects of Blade Inlet Angle on Flow Field of Centrifugal Fan

The effects of blade inlet angle on flow rate of centrifugal fan were numerically simulated using CFD software CFX. In this research, a total of six numerical models were prepared by combining different values of blade inlet angle. The frozen rotor method combined with realizable k-epsilon turbulence was used to simulate the three-dimensional flow inside the centrifugal fans. The results show that with the increase of blade inlet angle, its efficiency and output power decrease at small flow rate and increases at large flow. The total pressure and shaft power increase with the increase of blade inlet angle. CFD investigation showed that the blade inlet angle had a strong effect on the flow rate; It is found that the blade inlet angle play an important role for fan performance.

Analysis and Evaluation of Wind Turbine Flow Field and Noise Simulation Based on CFD Software

CFD is the abbreviation of the computational fluid dynamics, which is widely used in engineering fluid simulation. Based on two-dimensional N-S equation and k-e turbulence model, this paper uses FLUENT software, finite volume method and SIMPLEC algorithm to do numerical simulation and analysis on flow field in centrifugal fan. In order to improve the efficiency and accuracy of calculation, this paper uses AutoCAD to establish the two-dimensional model of fan, and uses the structured triangular mesh to divide grid. Encrypting the blade can improve the precision and also save the computer memory. Through the calculation we get the internal flow field velocity and pressure distribution in the wind turbine, and get the power level cloud of internal noise in fan. It provides the technical reference for the optimization design of wind turbine.