UCI Rocket Project (Liquids) Pressure Testing Unit (PTU)
Background:
The UCI Rocket Project - Liquids is a collegiate level liquid rocket team that is working to design, build, and launch a bipropellant (liquid natural gas and liquid oxygen) rocket. Their current rocket, Preliminary Test Rocket (PTR), works by pressurizing a main composite overlaid pressure vessel (COPV) above 4200psi with nitrogen gas and filling two separate tanks with liquid natural gas and liquid oxygen. Upon launch, the nitrogen gas will force all of the propellants out of the injector, into the combustion chamber, and accelerate out of the nozzle to provide thrust.
In order to ensure the correct stoichiometric mixture of the propellants is obtained in the combustion chamber, the liquid natural gas and liquid oxygen piping systems are separate and regulated to different pressures. These regulators are a very important component on the rocket and need to work accurately every time. The UCI Rocket Project - Liquids team requires regular testing of these components to verify their results. Another important component on the liquid rocket is the main relief valve. This relief valve works by letting gas out of the system when it reaches a set pressure. It is attached to the COPV and will vent at 4500psi. The relief valve acts purely as a safety measure in case the tank pressure increases too much. Both the regulators and relief valves are tuned using a set of nuts on a thread that compresses a spring which will open or close at the set pressure. To get accurate pressure readings from these valves, different procedures are used. For the regulating valves, pressurized nitrogen gas will be fed through the regulator and the downstream pressure is read. This number is then compared with the correct value and the set nut is adjusted to increase or decrease the output pressure. For relief valves, the process is different. Pressure is slowly increased in small increments until the relief valve bursts open. This pressure is read and compared to the desired value. The nut is adjusted accordingly and the process is repeated until the valve is venting at the correct pressure.
These pressure tests are done while hooked up to a fixed tank of nitrogen gas. The maximum pressure on these bottles are 6,000 psi, while other bottles of 2,000 psi are also used. No other gaseous medium is used for pressure testing. This process of pressure testing components can be burdensome, since each change in pressure requires a vent, adjust, and refill process. The UCI Rocket Project - Liquids team has a working method of testing these regulators, but it is not compact and cumbersome to use. The team has reached out and asked for a redesign of their current pressure testing unit to make the process of pressure testing components more efficient.
Goal and Objectives:
- Final design choice (02/04/2023)
- Working CAD model of the finalized PTU with BOM (03/02/2023)
- Written Assembly guide (03/02/2023)
- Complete manufacturing guide (03/02/2023)
Team Bio:
Matt Sprinkle:
My name is Matt Sprinkle and I am a fourth year mechanical engineering student graduating Spring 2023. I will recieve a Bachelor's in Mechanical Engineering with a Specialization in Aerospace Engineering and a Minor in Materials Science Engineering. I am currently a Propulsion Engineer on the UCI Rocket Project - Liquids team and have been working on new engine development.
Nicolas Tran:
My name is Nicolas Tran, and I am a fifth year mechanical engineering student expecting to graduate spring 2023. In the past I have also worked in a team of three to complete the design of a steerable mechanical walker in Fall 2022 https://projects.eng.uci.edu/projects/2022-2023/steerable-mechanical-walker.
Caitlyn Yang:
My name is Caitlyn Yang and I am currently pursuing a B.S in Mechanical Engineering with a minor in Materials Science Engineering expecting to graduate Spring of 2023. I lead the UCI Rocket Project (Liquids) Launch Vehicles Team on Dual Deployment Recovery Systems & Vertical Assembly and am the founder of Grasshopperfund, an edtech & fintech platform providing coaching, community and capital to youth-led startups.
Anthony Truong:
My name is Anthony Truong and I am a 4th year looking to obtain a degree in Mechanical engineering with a specialization in Aerospace Engineering. Other projects that I have been a part of was for the Crystal Cove Conservancy where I primarily looked at sea floor data and bathymetry to help come up with a design to combat cyclic erosion caused by ocean waves. This is my first time working with a project of this scale so I am excited to see what comes out of it!
Team Contacts:
- Team Lead - Matt Sprinkle (msprinkl@uci.edu)
- Sponsor/Advisor - Xian Shi (xianshi@uci.edu)