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Date: Tue, 18 Dec 2007 22:01:39 -0500
From: Ernest Christley <echristley@nc.rr.com>
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Subject: Re: [FlyRotary] Re: Supercharging
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Ed Anderson wrote:
>
> However, this is a really back of the envelope calculation which even 
> if correct does not taken into consideration any losses.
>
> Perhaps a more realistic approach is to consider  what size electric 
> motor does the fan blade usually have mounted to produce that 600 cfm 
> flow?
>
I believe this is the page that first sent me down this road:

http://www.lawncare-business.com/leaf%20blower%20comparisons.htm

The Husqvarna 155BT.  A backpack blower that uses a 3.0Hp engine to 
deliver 378CFM at 161Mph.  Their 165BT takes 4.2Hp to giver 452CFM at 
168Mph.

MacKissic uses a 6.5Hp engine on their LB6 push blower to deliver 
1800CFM at 175Mph.  10Hp will get you 2000CFM at 200Mph with their LB101CEZ.

Shindaiwa advertises that the 3.9Hp in their EB630 will deliver 613CFM 
at 201Mph, and Tanaka claims 500CFM at 200Mph from their 2.5Hp TBL-4600.

All the airflows are with the tube attached, but they are also marketing 
numbers, so keep the salt shaker handy.  In fact, given Ed's math, I 
would say that Tanaka's claims are miraculous.  Lynn gave me an idea for 
a test, though.  I'll borrow Mark's digital pressure meter and see how 
much static pressure my electric blower will make.  Possibly useless / 
possibly interesting data point.