Agenda for tonight’s meeting:
- Tentative schedule for prototyping, cold gas flow & static fire test
- Sensors for cold gas
- Locations for cold gas flow – GTL?
- Blast chamber
- Teach for SPARK
- New website
Issues with Pyralis Design
Jeff brought to our attention that having hot graphite (around 1200 Kelvin) on top of a piece of steel in the throat of the aerospike will lead to a potential softening of the steel, and the throat may expand. As a result, the characterization will change. We should pay attention to this potential issue.
Can 4mm wall thickness deal with combustion instabilities? If there’s a combustion instability, what type of moment will that exert on the tungsten rod?
General design quantities: combustion pressure about 4.5 MPa
See Gantt Chart. Might need to extend time for fabrication of cold flow test, sensors, test stand, and system integration
3 Sensors for Cold Gas
• Mass flow (approximately 600 m/s)
• Chamber pressure
• Schlieren photos?
• Pressure ports along spike
• Ambient pressure
• Wall strain
3.1 Schlieren Photo Setup
Possible to build our own setup – need parabolic mirrors and cost about $500. This is definitely something to consider.
4 New Website
We have a web designer – Corey Walsh. He and Norman can work together to update & upgrade website. Django? PHP? WordPress? Make it so anybody can upload a gallery of photos or videos.
Matt has put together a lecture for introduction to rocketry if we want to teach a topic about rockets. There is some interest in teaching a class.
6 Lab Clean-Up
Let’s tentatively aim for a major lab clean-up to be during Veteran’s Day weekend, after the 10/19 launch date. Hopefully, most of the members will be able to help clean up the lab. To build the new dust room, we should tentatively aim to do upgrade the lab right after Level 1 certification launch and during engine design review (before we start any major fabrication and manufacturing in RT Labs). Therefore, let’s aim for the beginning of November.
7 Igniter Possibilities
We should definitely aim for a non-consumable igniter for convenience.
• Spark plug – need to be careful where you place it. If mixture ratio isn’t right (if one region is oxidizer rich), might not ignite, and since this is a fuel rich process, the spark plug will be covered in soot and won’t work well afterwards. Nitrous oxide might be harder to ignite since a higher activation energy, so will spark plug still work?
• Compression caps (”the type that burns and you just have to aim it”)
• Solid rocket igniter – burn solid to start but will need to replace igniter every single
• Electromagnetic igniter
8 Action Items
• Check with Hannah for WPI blast chamber and contact Professor Dembsey about new
fire protection lab in Gateway.