Optimization And Experiment On Small Centrifugal Fan Impeller Structure

Since air-assisted plant protection machinery has the advantages of flexible and convenient operation, high work efficiency, uniform spraying, etc, it is widely used in the prevention and control of our country’s agricultural production. To meet the country’s agricultural subsidies, domestic production enterprises to accelerate the development of plant protection machinery breeze. At present, the total production and total sales volume knapsack sprayer duster in the country are the majority. Small high-speed centrifugal fan is the key components of knapsack air-assisted plant protection machinery protection machinery, so its performance has directly influence onatomization performance, spraying behavior, operation efficiency and economic performance of the whole machine.Now the study about the structure of centrifugal fan used in plant protection machinery is basically a blank. Firstly, we use Proe/E software to establish 3D modeling centrifugal fan. The internal flow field of centrifugal fan is simulated and analysis by using FLUENT, and the force condition of the impeller is analyzed in ANSYS software. These data will provide theoretical basis for optimizing the design of plant protection machinery centrifugal fan.The main contents and results of this paper are as follows:1. Study about the numerical simulation of centrifugal fan. Establish the model of original fan which is based on the currently exist centrifugal fan, then analyze the original fan in FLUENT, the result as a basis for subsequent comparison.2. Building the different models which have different outlet installation angle blade, blade outlet installation angle, centrifugal fan models impeller width, number of leaves, leaf thickness, leaf type and other structure parameters in Proe/E software. Those models are the foundation for subsequent analysis performed FLUENT and ANSYS.3. Through different turbine models FLUENT analysis, then compared with the original fan’s numerical simulation results. Through the compared with the different parameters for the fan total pressure, static pressure, speed, etc. in order to carry out the fan optimized design provides a theoretical basis.4. The number of blades, blade thickness, blade angle and blade inlet outlet mounting installation angle on the fan performance impact is relatively large, select these four factors orthogonal experiment. Choose the total pressure efficiency centrifugal fan for evaluation and use the poor value determines the relationship between the primary and secondary influence factors. We get the best combination of the fan structure parameters are: number of blades 32, import installation angle of 90 °, outlet installation angle of 145 °, blade thickness 1. Compared with the original fan blower optimized air volume increased by 3.92%, efficiency is improved by 17.07%.5. According to the results of the stress analysis in ANSYS, we can get the conclusion that the stress on the connection between the vane and wheel disk is more concentrated and the displacement of the outer edge of the vane is larger. You can consider increasing the thickness of the blade to increase the structural strength of the impeller.