Livestock fanThe noise is too high, not only disturbing the people, but also failing to meet the environmental protection requirements. How to reduce the noise9Click to start

　　1.Reasonable choice of fan type

There are many types of fans. No matter what kind of fan, it is necessary to choose the appropriate type according to different environments. In the same type of fan, the air volume and pressure are large, the excess is too large, and the noise is too large. This is not only a waste of electrical energy. And increase the noise. Therefore, for the same type of fan, as long as the performance allows, the fan with low speed should be selected as much as possible. For different types of fans, when comparing the noise, the specific sound power level or ratio should be selected.AThe sound level is low as an important condition, and not only the rotation speed and circumferential speed should be considered.

　　2.Reasonably design pipeline

The resistance of the pipeline should be small, and the inlet of the fan is not easy to be in the flow field several times. If there are many pipe fittings in the system such as elbows, branch pipes, etc., the distance between them should be opened5-10Double the pipe diameter, adopt a reasonable adjustment method, and make the air intake of the livestock fan evenly reduce the noise. In addition, the vibration of the casing and the pipe should be prevented from excessively radiating excessive noise to prevent cavity resonance.

　　3.Influence of the gap between impeller and volute on noise

The volute gap has a great influence on the rotation noise. When the volute gap is small, the noise is high. As the gap increases, the noise decreases. Due to the different volute gap, the sound pressure level of the same fan at the appropriate working point is about the same18decibel

　　4.Noise reduction effect of inclined volute

Increasing the snail tongue clearance or tilting the snail tongue will reduce the rotation noise well, and at the same time, the vortex noise will be slightly reduced, but the effects of the two cannot be superimposed.

　　5.Boundary layer automatic blowing

　　6.Turbine inlet and outlet with turbulent flow net

Install a turbulent flow net at the inlet of the impeller. It can improve the airflow inlet conditions, and form small-scale turbulence behind the mesh, accelerate the boundary layer turbulence, make the separation point move backward and the support body area is reduced, so that the vortex noise is reduced.

　　7.The double-layer volute is filled with glass wool in the middle, and the inner wall is opened to absorb the impulsive force of the uneven air flow from the impeller and the turbulent pulse power in the shell.

　　8.The blade surface coating fan blades using porous materials can reduce noise.

　　9.Using a rotary diffuser to reduce the noise of centrifugal fans. Using a rotary diffuser on the radial and forward fan impellers can not only reduce the noise of livestock fans, but also improve the aerodynamic performance of fans.