Industrial large fans are commonly used cooling and ventilation equipment. Through the rotation of the fan blades, a large amount of airflow is pushed to the ground, forming a horizontal movement of the airflow layer at a certain height on the ground surface, thereby realizing the overall air circulation system of the space, exchanging the airflow indoors and outdoors, And reduce the body surface temperature. The blades of industrial large fans are an important structure for airflow movement. The blades are usually made of light and durable materials to ensure the hardness of the blades and the overall quality of the fan. The design structure of the blades will affect the performance of industrial large fans. , then, from what aspects do fan blades affect the performance of industrial large fans?
1. Fan blade pitch
If the distance between the blades of the industrial large fan is too small, it will cause airflow disturbance, increase the conflict on the blade surface, and reduce the ventilation efficiency of the industrial large fan; if the distance between the blades is too large, the pressure loss will increase, and the wind pressure will not be enough An effective horizontal movement of the airflow layer is formed. Therefore, when designing and manufacturing fan blades, it is necessary to plan the correct limit of the blade spacing of industrial large fans.
2. The number of fan blades
The number of blades commonly seen in large industrial markets is 5, 6, 8, etc. If you choose an even number of symmetrical blades and do not adjust the average coefficient, it is easy to cause resonance in the fan blade system. If the blade material cannot resist vibration The resulting fatigue will cause problems such as blade or mandrel fracture. Therefore, the design of the blades of large industrial fans on the market mostly adopts an odd-numbered asymmetric form to achieve the purpose of weakening resonance.
In addition, the greater the number of fan blades and the faster the rotation speed, the greater the air supply volume, but the greater the corresponding power consumption. Therefore, the number of fan blades needs to consider various factors and choose an appropriate number.
3.Fan blade smoothness
Smoothness is an important index to evaluate the characteristics of the unevenness of the material surface. This is an index not affected by design factors, and basically depends on the manufacturer's mold forming and post-processing technology.
Outside the design curve, the unevenness of the blades will cause turbulent flow during the rotation process, increase conflicts, reduce the ventilation efficiency of industrial large fans, damage the functions of the fans, and increase the working noise. Therefore, the smoothness of the blade surface must be strictly controlled during manufacture to ensure that its smoothness meets the design requirements of industrial large fans.
4. The blade material of the fan blade
Large industrial fans usually use aluminum alloy to make fan blades. Because aluminum alloy has good toughness, it can resist a certain degree of physical deformation. Aluminum alloys will also vibrate due to the force in the process of pushing air, but the amplitude is usually smaller. Another common type of vibration is due to the uneven distribution of the quality of the blades and the eccentricity between the center of mass and the center of rotation. When the area (quality) or eccentricity of the fan blade is large, it may cause vibration of the large industrial fan or even the overall radiator, which will affect the performance of the fan.
5. The blade form of the fan blade
The blades of common large industrial fans are of equal cross-section, while the blades are designed with the cross-section of the airfoil, and then follow the design requirements, and rotate and stack according to the angle between the root and end of the blade and the rotation axis, and the width of the root and end. Form the three-dimensional fan blade surface and perform curve fitting to realize the design of the fan blade model and manufacture a streamlined fan blade with variable cross-section that is more in line with the principle of aerodynamics. This form of fan blade can drive more flow of air when it rotates, and enhance the horizontal movement intensity of the gas, thereby improving the ventilation effect of the fan.
6. The blade curvature of the fan blade
Within the specified limits, the greater the curvature of the blade, the greater the kinetic energy of the gas at the same speed, that is, the greater the air volume and pressure; at the same time, the greater the resistance on the blade, the greater the torque required for the motor.
The above is the introduction of relevant knowledge on which aspects of fan blades affect the performance of industrial large fans. The fan blade occupies an important position in the overall structure of the industrial fan. The design of the fan blade needs to consider many factors. Any factor in the manufacturing process of the fan blade will affect the overall operation of the industrial fan.