orifice plate leaking

[bruce]

All this talk of variable orifice holes and such I have two words to say;

Pitot flowbench

Solves all those problems

[larrycavan]

[bruce]

Ah that would be true . . . ok forget what I said.

I'll leave you orifice guys alone now . . . I have testing to do.



Edited By bruce on 1134830991

[Mousehouse1]

[cboggs]

[Mouse]

[larrycavan]

[Thomas Vaught]

Guys, the 1020 has the ability to do exhaust flows with the same movable orifice so I am sure that they have programmed in a set of instructions for what values are needed when the unit is in "exhaust" mode.

I do not know "exactly" what the movable orifice looks like as far as sharp edges, any radius on the parts, etc. I will ask Harold but he might not tell me that info though he has passed on all the other info over the years freely.

Tom V.

[Thomas Vaught]

CBoggs, using the 100, 200, 400, 600 holes in the plate is KNOWN technology and has been around since the first SF1200 benches were created. I added the 100 cfm hole but that did not change the basic design, just refined the ranges.

Good luck with your project.

Tom Vaught

[Nick]

Pilots Suck, and belong on air planes. Who wants to monkey around with correction factors, every five minutes. What happens when crap gets stuck in you fancy pilot holes. I can wet flow. I can smoke test, I can suck clay in my bench if I want. I can suck my french fries in mine if I want. I can go from 25cfm to 1100cfm with one bench, how many different Tubes do you need to accurately test to 1cfm? How about cost, your flow receptacles are 300 bucks, my orifices cost me $15. This is a Ford VS Chevy deal. You just don't talk about your problems. Doctor Phil says, "You cannot change what you don't admit" Pilots have just as many issues as orifice benches. IF pilots are so much better, why do you use an orifice plate to calibrate your pilot bench? Your not fooling this Cowboy.

I should have been a Lawyer, I love to debate. we should make a Pilot VS orifice topic and let everyone chime in. Who wants to be the Judge?


Nick

[Jesse Lackman]

Here Nick, read this;



That discussion is what made me decide to go to a pitot flow section, specifically what ozrace has to say. When he drops a picture of his bench in page three what he's been saying is validated be because the design and craftsmanship is stunning. It is so original, there is nothing like it out there. I got more pictures of that bench while under construction, it is simply amazing.

BTW the "rbkarter" on that thread is Rick Blood, the guru of the Meriam laminar flow bench.

If I were to go orifice I would put it in a pipe which is something I could easily do given the fact the flow element will be mounted externally on the bench I'm building. I should try both pitot and orifice, just to see what is best.

Either of these would be hard to beat though;

[Jesse Lackman]

[bruce]

Ah my averaging pitot tubes are let me see . . . less than $20 each? And they are quite accurate for a home built bench. Changes of 1 cfm are realistic attached to the FP1 which takes care of all the correction factors. All I do is input the temp and baro and it does all the rest. One time calibration, change the tubes out to match what you need to test (with the FP1 this is probably not even required, I have never maxed it out yet). I have tubes 1.5", 2" and 3" usually never change from the 1.5" one for the testing I do. I work with alot of low lift testing for stock engines.

Yes the orifice bench would let change for a wider range of testing alot quicker, comes down to what you are testing and what will work for you. Orifices are effected over time by wear to the sharp edge so your Cd is going to change so calibration is also a factor with that style.

I'm sure a good arguement could be had for both sides, they all have pros and cons . . .

[gofaster]

[Thomas Vaught]

Quote:

"LFE bench zealots brag that the LFE bench will pick up someone walking by the bench. That doesn't seem to related to high CFM - high test pressure flow testing reality."

I like the new demo that Super flow puts on using their 1020 automated bench with the electronic display on the Laptop screen.

They have a filter (like a K+N) over the inlet hole and request 300 cfm out of the system.
The system reads the cfm based on the DP across the filter element and the DP across the Diamond orifice and maintains 300 cfm through the system.

Harold Betties takes a dime out of his pocket and rests it against the side of the filter element. Basically .371 sq inches of area change in the total area of the K+N filter and the bench will respond and change the speed of the motors to compensate. Pretty cool demo.

Tom V.