This update is pretty late, as this occurred at the end of November 2017, before I headed out of town for my summer internship. I have not been able to do any testing since but am just now revisiting the igniter as I am back in town and at University again.
After my first initial hot fire semi-success I was on a good high and happy everything worked. In order to show some friends how cool this was, I set up in the exact same manner as before and attempted another hot fire, this time I was unable to light the igniter.
The inlet pressures and valve timing were all exactly the same, the only difference I noted was the spark plug had eroded, this was replaced and tried again. No ignition.
After talking to others over the summer I have a rough idea on how to proceed,
- Switch from swirl fuel injection to 90deg with ox
- 3D print (with SLS) smaller and more precise orifices that will press fit in my 1/8 nipple fittings
- Future version, move inlets further away from spark plug to help prevent erosion or lengthen hole so does not protrude into chamber as much
I’ll start with the orifice fix and go from there. One other thing is that for each test I need to hire an O2 and N2 bottle which is a bit costly for me as a poor student, I am seriously thinking switching fuels from Ethanol to a gas like methane for example. This would alleviate the N2 and only require buying a mini disposable gas canister from the hardware store. Thus enabling me to test more often and gain experience much quicker.
I also have borrowed a NI Labview DAQ module, so I will also work my way towards converting the avionic system over to this. Labview for students here I come!
Video Cation: After 4 years of development, WARR performed the first hotfire tests of Europe’s most powerful cryogenic hybrid rocket engine. With 3kg/s of liquid oxygen massflow, the “Battleship” generates 10kN thrust for up to 15 seconds burn time. The design point of 20bar chamber pressure was nearly hit and valuable performance data was collected for further improvements. The two-week campaign included verification coldflows, ignition checks and four hotfire tests with 5s, 10s (2x) and 15s burn time.
Special thanks to all members of the WARR Ex-3 Project as well as the members of the M11 Test facility at the German Aerospace Center (DLR) Lampoldshausen for the support and guidance. This project was funded by the Federal Ministry for Economic Affairs and Energy (BMWi) during the STERN Project.
Please note: We are predominantly master students of mechanical & aerospace engineering and spend most of the time before tests on calculations and preparations to prevent severe damages on material and personnel. Please don’t feel inspired to light your own rocket motor in your backyard. Rocket science is a serious issue – if you get the numbers wrong, people die. You have some experience in mechanical/electrical engineering and want to participate, become part of the team? Feel free to send your application to firstname.lastname@example.org
Boston University Rocket Propulsion Group recently test fired their Iron Lotus rocket engine. Developing ~2500lbf (11.1kN) of thrust, the engine was tested for 1 and 3sec burn times.
As the name implies, the engine is a steel heat sink engine, not intended for long duration firing and primarily used for ignition testing, before the (flight) regen Lotus Dev 2 engine is tested.
That sound and echo are impressive!!
Video Caption: A Short preview showing a few seconds from the second parachute test at Skydiving Center Jump.
This test was to investigate a mechanical “disreefing” device, that help us control how fast the parachute opens up.
Look like we will see another hot fire of the Galactic Aztec Heavy on Feb 4th. The last hot fire conducted by the team saw the LR101 engine run rich as it had a burn through at the throat. The team have since been able to obtain more surplus engines to enable the rocket to see flight!
A few new updates from the SDSU Rocket Project over on Facebook.
Today Rocket Project completed a successful test of part of our recovery system. This specific mechanism will allow for a dual-deployment parachute system without the need for multiple large recovery charges.
The SDSU Rocket Project have been making steady progress on their new rocket, with the recent completion of heat treatment and hydro testing of their aluminum tanks.
You can view the whole Facebook album here for many more pictures.