PTS Flowbench Forum

All that so you don't need a slide plate reversing valve and a motor speed control?

Nice work grey, i too have a hard time giving up on some projects i just get overly vested

I sure hope this works for you.

Rick.

PS. Have you thought about using some sort of averaging tube for the DP pickups like a 1/8 piece of copper fit it the corner following the perimeter of the box with like a .020 hole every 4 inches?

1960FL wrote:All that so you don't need a slide plate reversing valve and a motor speed control?

I was under the impression this was going to be a cheap get the thing running deal, but if the owner told me he wanted top notch at the start, I would've gone the full hog to begin with.

1960FL wrote:PS. Have you thought about using some sort of averaging tube for the DP pickups like a 1/8 piece of copper fit it the corner following the perimeter of the box with like a .020 hole every 4 inches?

I might actually try that because I have nothing to loose at this stage

1960FL wrote:All that so you don't need a slide plate reversing valve and a motor control?


PS. Have you thought about using some sort of averaging tube for the DP pickups like a 1/8 piece of copper fit it the corner following the perimeter of the box with like a .020 hole every 4 inches?

I made an averaging tube of a similar arrangement in a bench that I built. It was on Tony's recommendation and it steadied out the static numbers quite a bit.
The upper plenum in an orifice bench has a heap of good and bad areas to test from in my opinion, if you can average them before they are measured I think your better off.
The way I proved it to myself was probing with a pitot through the test hole into the upper chamber while the bench was running unrestricted. Hmmmmm surprising it was.

Jim

Well it's official, 8 old second hand motors don't add up to that much.

300 cfm PAP with the bench flat out.

Hotz wrote:Nice job...I love it

I second that That is sweet!

Old Grey wrote:Well it's official, 8 old second hand motors don't add up to that much.

300 cfm PAP with the bench flat out.

Grey...You should be rewarded for your hard work. I'm off to new things now so I'll give you some VBA source code to add some features to your FP1 based program if you want it. Email me.

Off topic but here's a peek at the beta version being used dial in the proto box.

larrycavan wrote:Off topic but here's a peek at the beta version being used dial in the proto box.

Nice sheet. I like the pretty stuff because it gives that air of professionalism.

Old Grey wrote:Here are my ludicrously over designed control valves - stop laughing -

I kind of got used to the bowls but I do have to admit that these valves have a much more positive control, better than any SF I have used.

I only did one flow on the head I'm using for testing and it looks like the bounce on the cfm is less(1.0 instead of 1.4), but the dep seams to be a little more bouncy(0.4).

I'm a bit distracted by the POS bench but I will play around on this one some more.

300 cfm PAP with the bench flat out.

Grey, Try the same test with like a 600 CFM internal orifice and see what you get.

Rick

Old Grey wrote:

Old Grey wrote:Here are my ludicrously over designed control valves - stop laughing -

I kind of got used to the bowls but I do have to admit that these valves have a much more positive control, better than any SF I have used.

I only did one flow on the head I'm using for testing and it looks like the bounce on the cfm is less(1.0 instead of 1.4), but the dep seams to be a little more bouncy(0.4).

I'm a bit distracted by the POS bench but I will play around on this one some more.

Bounce is turbulence. Where that turbulence comes from remains to be seen. If the numbers bounce when flowing orifice plates then you have two possible sources to investigate.

1 - cabinet turbulence
2 - a flaky pressure sensor. [easily diagnosed]