Why can rotary vane fans maintain a constant flow rate, while centrifugal fans cannot? !
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Does the centrifugal fan have some compression, which is why it cannot maintain a constant flow rate? ! Please give me some advice.
It is related to the working principle and structure. Rotary vane fans are positive displacement fans, whereas centrifugal fans are blade-type fans.
How can it be explained in principle? Since the volume of a positive displacement fan remains constant, can it ensure a constant flow rate?
It’s a principle-related issue; I need to think about it: lol
Think about it and tell me. :victory:
One relies on centrifugal force to do work, while the other relies on compressing air to do work.
Positive-displacement fans have a flow rate that does not change much with system resistance (back pressure). For centrifugal fans, the actual exhaust volume is the intersection point of the system resistance curve and the performance curve; in other words, as the outlet pressure changes, the volume of air discharged also changes.
Then I’m puzzled: what is the inevitable connection between pressure and flow rate?
Positive-displacement fans have a flow rate that does not change much with system resistance (back pressure).
First, let’s take a look at the performance curve of the centrifugal fan. It’s fine to consider pressure and flow separately, but for a specific subject of study—namely, the fan—doesn’t each flow rate correspond to a corresponding exhaust pressure? How can you say it doesn’t matter? The operating point is the intersection of the system resistance curve and the fan performance curve. Make sure to understand the concept well.
Sigh. . . . . It’s really impossible to have a pleasant conversation with kids. I definitely know the basic characteristics of this centrifugal fan. I want to know why centrifugal fans have such characteristics!