PSAS/ news/ 2003-12-21

Hybrid Meeting Minutes 12/21/03


In attendance: Tim B, Brian O’Neel, Jim Ward

Topics Discussed:

The meeting was more of a work party today. We focused on getting the gaseous oxygen motor ready for test firing on the 31st of December.

The following items were worked on:

Jim W. completed the connector/adapter for the Flextek to breadboard connection that will allow us to test out the functionality of the control board. Andrew G. and Tim R. are currently working on the interface board that will go between the Flextek controller and the oxygen solenoid, nitrogen solenoid and igniter. The interface board will use IPS5451 “intelligent MOSFET power switches” to drive the solenoids and igniters. The completed control system should be ready to test in a couple of days.

Brian O. worked on coming up with a way to light the paraffin. It will use a small ring of solid AP/HTPB propellant at the injector end of the motor. 2 seconds prior to initiation of oxygen flow the ring will be started. (See movie below). This will hopefully insure successful ignition even in the presence of the initial oxygen blast the motor will experience.

Tim B and Brian O. worked on testing the pneumatic actuator. We were able to use the compressed nitrogen source to open remotely open the ball valve and allow a 850 psi stream of oxygen to flow through what we have completed of the plumbing system.

Still to do:

Tim committed to also (along with Evan) doing the metering orifice calculations for choked flow and will have them completed in a day or so. (Calculations are finished AFAIK: Oxygen metering orifice design)

Jim will work on the control script for the Flextek controller.

Brian will continue with integrating the plumbing and machining of the nozzles.

We still need the following:

  1. Awaiting arrival of Nitrogen purge solenoid. (Hopefully arriving in the next day or so)

  2. Exchange Argon tank for Oxygen tank. (Brian)

  3. Exchange CO2 tank with Nitrogen tank. (Jim W.)

  4. Integrate metering orifice in with the rest of plumbing. (Brian)

  5. Attach oxygen braided feed hose to injector/diffuser

  6. Bolt and Weld analysis (Peter)

  7. Machine 3 nozzles of different sizes (Brian)

  8. Pour at least 3 paraffin grains

  9. Hook together plumbing. (Brian)

  10. Machine new replacement flange and o-ring groove. (Brian)

  11. Weld combustion chamber. (Evan)

  12. Build a test stand.

  13. Integrate all the electronics and hardware. (Jim W.)

  14. Find a test fire location