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In the design of the centrifugal fan, the need to consider the body structure, volume flow, working medium temperature and density, and sometimes need to take into account some special requirements and so on. Therefore, we should first understand the centrifugal fan of the general design requirements, in order to carry out a reasonable design, to avoid mistakes.
The requirements for centrifugal fan design are generally: meet the required flow and pressure conditions should be in the vicinity of the highest efficiency point; the highest efficiency value should be as large as the efficiency curve flat; pressure curve stable working range to wide; fan structure is simple Easy to operate and easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate, easy to operate , Easy disassembly and transportation.
In fact, it is generally impossible to meet all of the above requirements, for example, there is often a contradiction between aerodynamic performance and structure (strength, process). The solution to the contradiction is to seize the main contradictions to coordinate the solution, which requires designers to choose a reasonable design. Centrifugal fans use different requirements are not the same, such as public buildings used in centrifugal fans are generally used for ventilation, the most important requirement is the low noise, multi-wing centrifugal fan with this feature; and require large flow Of the centrifugal fan is usually double suction type; for some high-pressure centrifugal fan, than the low speed, the relative proportion of its leakage loss is generally larger.