Projects
Cold Flows
A cold flow is very similar to a static fire test, but instead of propellants we utilize LN2. This test is done to prove the efficiency and consistency of our fluid systems. This test has a multiple step process and is procedurally done to record the overall status of the rocket.
Propulsion Specialist and Dewar Operator
I serve as the teams Propulsion Specialist and Dewar Operator. My responsibilities include ensuring valve states, solving fluid systems issues, and determining the efficiency of actuation systems. I communicate with the Avionics team and lead each step of the test making changes where I see fit based on either issues or successes. I physically carry out the test by assembling the components, pressurizing the COPV, and operating our LN2 dewar to chill and fill our tanks in order ensure the current state of the entire system.
Cold flows signify both the rocket's performance and our own performance as engineers. With this I had the opportunity to test myself on knowing the procedures and gauge my leadership prowess. This includes following the steps, communicating with Avionics Engineers, and improvising when problems arise. These tests occurred frequently in order to train us for future Vertical Test Fires and launch.
One of my tasks also included certifying our fill valves. These valves will be the direct link between our tanks and the propellants. Given our rocket will be in the upright position the fill valves are under tremendous stress. The pounds per force of the propellants and pressure from the COPV will put great stress on the valves so they must be able to hold without leaking when pressurized and open clearly so propellants can get through into the tanks. During pressure building they will be under great stress, so to combat this I decided to implement a vent port into each ball to reduce the stress by giving the propellants a place to go. This distributes the pressure so it doesn't go right onto the wall of the ball. But during the machining process there is a liklihood that the ball will deform and thus leak when in the closed position. Given this I would put each fill valve through cryogenic pressure testing after machining to certify that it is cold flow and test fire ready.
Bleed Valve Actuation System
The Bleed Valve Actuation System (BVAS) is an evolved form of our manual bleeds which need to be opened and closed when in the vertical position. They are very frequently used during cold flows, vertical test fires, and will be during launch. The goal of its design is to ensure safety with an easier form of control that does not involve sending one of our engineers to manually close it. To combat these issues my team and I came up with a solution that involved a pneumatic actuator. Its design is similar to our Main Valve Actuation System (MVAS), and each valve will have a single pneumatic actuator that will open and close on command by the avionics engineers.
After completing the design I tested its performance under cryogenic conditions and it successfully actuated and held pressure. This component has since been proved as a possible future Main valve and bleed valve because of both its performance and simplicity
Component Testing
Given this is an engineering project and team, components will break. They'll be overused and sometimes straight up stop working. If something goes wrong in a cold flow or test my responsibilities include figuring out what went wrong and how to fix it tendered to the situation. When these issues arose I would lead tests and give procedures to my teammates so that we can solve the issue and re-certify the given component. These certifications are done daily in order to yield good results in high stakes tests such as cold flows and test fires.
Some examples include:
MVAS Troubleshooting
After multiple cold flows our Main Valve Actuation System began to freeze over and not open when commanded. So I conducted a test that would put MVAS under those conditions so the issue can be clearly observed. This test was designed to insert a bleed above the entrance to MVAS on the rocket so we could be sure LN2 was truly in the component and could get true results.
Leaks
When our Helium bleed valve leaked during a cold flow I was tasked with confirming what was wrong. I tested it under high pressure and confirmed the leak. I then disassembled it and replaced the NPT. Once this was done I re-pressure tested it and found no leak. I then implemented it back on the rocket and this yielded a successful cold flow days after. This procedure is done on many components that have leaks and it quickly rids our system of unnecessary pressure loss.
