Using bleed valve on CRE/PTS style bench

[stef-1]

Hi, I'm in the process of building at little flowbench for home use in my garage. It is a mix of CRE's bench and details from the PTS plans. It is a small bench with just four motors because of power limitations in the garage.
I'm thinking of using a throttle body as a bleed valve for depression control, mounting it on the lower chamber of the orifice box. Now I'm not sure if this is okay and if it will alter how the bench reads. Should I add an extra chamber in the bench to isolate the bleed valve or would it be okay attached to the lower chamber?

This is a pic of CR's bench below, mine will look similar;

[thomasvaught-1]

You have 4 chambers:

Top chamber with the orifice plate = #1

Second chamber under the orifice plate = #2

Third chamber (Inlet side of Motors) = #3

Fourth chamber (Outlet side of Motors) = #4

Put the Bleed valve in the center of the back wall of chamber #2 (with an air deflector above the bleed valve hole) and you will be fine.

The bleed valve will not affect the accuracy of the ratio between the test part and the orifice plate in this location. Superflow Benches and the PTS designed bench are both "ratiometric" benches.

Tom Vaught

ps You might be able to add a piece to your "lower" deflector
if the lower deflector is high enough in the chamber

[stef-1]

Thank you Tom