Over the last year I have been working on a 3D printed spark torch igniter, this has been a little side project while at university and eventually the experience gained will lead to this or a similar igniter used to light the main chamber of my rocket engine.
Yesterday I achieved the first hot fire tests of the igniter, the final test is shown below.
I ran through three hot fire tests, tuning it a bit each go. As can be seen, it is currently running oxygen-rich whereas it was designed to run fuel rich, the flame is too blue.
The design chamber pressure is 70 PSI, in this test it is ~85 PSI, so still some tuning of the inlet pressures required.
Before this test I had to replace a solenoid with another I had that has a smaller orifice than the fuel orifice on the igniter, although there is only 0.1mm difference this could slightly affect the performance. In the future, I will implement different sized orifice fittings to help fine tune it as I am not 100% on the size of the 3D printed orifices in the chamber.