Re: wind speed

Re: wind speed   (07/23/2008, 1:09 PM)

You need to know the size of the fan or the area of the wind tunnel.

Let's say you have a box fan that is 4 feet square.

Since you have 26,000 cfm, then in each square foot of area, you have a velocity of 26,000/4 = 6500 feet per minute.

You can then use this page to convert from feet/minute to mph:

https://www.convertunits.com/from/feet/minute/to/mph

1 mph = 88 feet/minute

That means 6500 feet/minute = 73.86 mph.

So in our example, with a box fan that has an area of 4 foot square, you find that 26,000 cfm translates to 73.86 mph wind speed.

For an arbitrary fan of size X square feet:

mph = cfm / (88 * X)