In industrial production, the use of fans is inseparable. Especially in many production industries with high gas transportation and ventilation requirements, centrifugal fans with higher pressures are mostly used. However, in some cases, it is difficult for a single fan to meet the gas requirements. Due to the transportation requirements, multiple units are required to work at the same time. The main working mode is series and parallel operation. What is the series operation of centrifugal fans?
1) Serial operation of centrifugal fans
When a single centrifugal fan cannot meet the requirements of the conveying task, the parallel or series operation of the fans can be used. The so-called series operation refers to the working method in which the outlet of the previous centrifugal fan transports the fluid to the inlet of the other centrifugal fan, which can improve the efficiency and save energy. From the continuity of the flow, it can be known that when the centrifugal fans are running in series, the sum of the flow through the two fans equals the total flow of the system, and the sum of the pressure differences between the inlet and outlet of each centrifugal fan is the total pressure of the system. The series operation of centrifugal fans is mainly divided into the operation modes of the same suction, the same row, and one suction and one row, which need to be selected according to the actual situation.
2)the characteristics of series operation
1. After the centrifugal fans are connected in series, the original suction characteristics of the fan can still be maintained, with stable operation and stable performance.
2. The pressure of centrifugal fans in series operation basically satisfies the superposition principle, but as the pipeline resistance is small, the actual performance curve and theoretical performance curve of series operation are gradually separated, and the gap between the two tends to increase, and the actual pressure of series operation is less than the theoretical pressure. .
3. The total power of centrifugal fans running in series is less than the theoretical superposition power.
4. The centrifugal fan is suitable for operation under the condition of large pipeline resistance. When the pipeline resistance is large, the pressure and efficiency of series operation are greatly improved, and the series effect is more obvious.
3) Precautions for series operation
1. When the centrifugal fans are connected in series (one suction and one row), if the pipeline resistance between the two fans is relatively large, that is, when the flow rate is relatively small, increasing the speed of the two fans can significantly increase the speed of the two fans in series. Efficiency, that is to say, the energy input into the series system is effectively utilized to a greater extent at this time.
2. If the speed of the two fans cannot be increased, the resistance in the pipeline should be changed according to the existing speed combination of the fans, so that the efficiency of the series connection can be kept in an appropriate range and the energy can be fully utilized.
3. When selecting the speed of the two-stage fan, the upper limit of the single-machine flow of the second-stage fan should be greater than the upper limit of the single-machine flow of the first-stage fan, so as to ensure that the fan in series can still play a role when the resistance is reduced.
Regarding what is the series operation of centrifugal fans, the above is all the content that Xiaobian has compiled and introduced for you, and I hope it can be helpful to you. In fact, the simultaneous operation of multiple centrifugal fans will inevitably cause a certain flow loss. For example, there will be a flow loss in the pipeline when running in series. At this time, under some working conditions, the performance of series running may not be as good as that of a single fan. , so you should pay more attention.