Fan Design 1

[dcharles]

I am studying on the Open University and for my project I am researching the topic of extractor fans, mainly the ones found in the home i.e. kitchen, bathroom etc.
I was wondering if anyone could help me out with any calculations or know of a website that can help me i.e. blade angles, pressures required, speed of fan, forces etc. that are needed to come up with a suitable presentation.

 

[insideman]

Charles: Fan design is not something that can
be capsulised in a paragraph or two.

First, decide what flow is needed and what pressure drop must be overcome. These two combined and an assumed fan efficiency will give you the power required. Then you can choose a motor to meet the power need. The motor will probably be an induction type with
a narrow range of speeds for best efficiency.
Select a working rpm. Then calculate specific speed.

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Enough from me. Get ahold of Steppanoff's book "Turboblowers" for more info. Or contact me directly.

 

[Rich2001]

Here is a starting point
LAU INDUSTRIES is a manufacturer of fans and blowers.

http://www.lau-ind.com/index.html

GoodLuck,
Rich

 

Stepanoff Blowers is OK, but desperately out of date. For a more modern treatment, refer to Axial Flow Fans by R A Wallis. You will find that you do need an axial flow machine, and this is not something that is well covered by Stepanoff. His other book Centifugal and Axial flow pumps gives a dumbed down design process which may more suit you needs.

 

I need just some basic calcs i.e. how deterimine the power needed, height of fan blade, rpm of fan, extraction rates etc it is only a basic project so I dont have to go into it in a complex manner. Just a few basic calcs would be apreciated.

Thanks


dcharles

 

[younggerry]

Type "fan equations" into yahoo and I think that you'll find enougn to get you started.