Two or more centrifugal fans inhale from the same intake duct or inlet chamber, and at the same time breathe air into a common pipe in parallel, which is called the parallel operation of the centrifugal fan. In the process of using two typhoon machines to run in parallel to a certain extent, the influence of the same type of parallel operation is different.
The two parallel centrifugal fans are of the same type, so that in parallel connection, the method of obtaining the parallel characteristic curve of the centrifugal pump can be obtained effectively according to the parallel characteristic curve of its centrifugal pump, that is, according to the wind pressure after the parallel connection, Based on the principle of superposition of the air volume of the two fans in operation, the characteristic curves after parallel connection of the fans are obtained by means of graphic method. The analysis shows that the air volume and wind pressure in the system increase after parallel operation. However, after parallel operation, the supply volume of each typhoon equipment is less than that of one typhoon machine.
To some extent, the centrifugal fan needs to be considered synthetically on the basis of its actual conditions in the process of selecting equipment because of its different production requirements and working conditions, in order to meet the actual requirements of the users. In the design of centrifugal fan equipment, it is necessary to design from the user's point of view. The first is to reasonably select the blade is a structural form.
Centrifugal fan should also pay attention to choose its suitable transmission mode, not only to consider the speed requirements of centrifugal fan equipment, but also to consider the working environment of fan equipment. In the case of high temperature and dusty working conditions, the protection and cooling of the motor and bearing should be taken into account in the selected transmission mode. Then on the volute shape size choice, generally speaking, volute shape size should be as small as possible.
The rotary number of centrifugal fan equipment is high, so it is suggested that the cochlear shape of centrifugal fan should be shortened to a certain extent, and the standard cochlear shape should be chosen for low specific rotary fan. Sometimes in order to reduce the volute size, the outlet velocity of the volute is larger than the inlet speed of the fan, and the outlet diffuser is used to increase the static pressure. The next step is to select the blade outlet angle. In fact, the blade outlet angle is one of the main geometric parameters to be selected in design.