Paul,

Designing the air pump follow some of the following.

1. Inlet to out let radius should be 3:1,

2. The exit area of the volute should be calculated to be the

maximum CFM you wish the air pump to have and the area is determiend

by the air velocity at the exit which is about 75% (est.) of the

outer tip speed of the disk pack you are using.

3. Disk spacing from .018 through .050 will be within 75% of each

other for efficentcy.

4. Back presure capability is just the mass x velocity / area of your

exit volute.

How many disks is a bit harder to calculate but relate to the volume

of air you wish to move and will take a little hit and miss. Try

using .025 spacings and disk width then skip disks if the air flow is

too low, make the out let orfice varible of adjustable. You most

likely are looking at a 8" or more disk size.

Dave

--- In

TeslaTurbine@yahoogroups.com, "Paul & Patricia Bartlett"

<pbartlet@k...> wrote:

>

> Hi Guys Help me out

>

> Here's something a little more to the point.

> I need a dust collection system for my shop. A Tesla pump would (I

> think) be a lot quieter than one of those impeller monstrosities. I

> want to use a 3650rpm 3hp motor. What OD and how many blades do I

need

> to use that power?