Nitrous Cold Flow (Water)

Completed:December 2020


In this test, we will run water pressurized with nitrogen gas through our nitrogen tower, mirroring that of our preliminary ethanol cold flow test. Our oxidizer, nitrous oxide, is self-pressurizing. This means that in a certain temperature range, liquid nitrous oxide will boil off and create a gas that exerts a pressure on the remaining nitrous oxide liquid. This means that unlike our fuel (ethanol), which requires a nitrogen tank to pressurize, nitrous oxide can pressurize itself and takes out the need for any K-bottle. However, since nitrous is a rather dangerous material, we have decided to first perform this preliminary nitrous oxide test where we replace the nitrous oxide with water and add in a nitrogen tank for pressurization.



Like the completed ethanol cold flow, the nitrous oxide (water) cold flow test includes tanks and a similarly structured test stand. However, since we want to mirror our current plumbing layout to that of the nitrous cold flow test (with nitrous), the P&ID looks a little different from that of the ethanol cold flow test.

The nitrous cold flow (water) will fill the water in the nitrous flight tank with hose water and a hydropump in order to model the ntirous cold flow filling procedures. By turning the nitrous storage tank upside down, the nitrous oxide will


So, what did the programming team do to help make the cold flow a reality? Well, hidden behind thousands of lines of elegant code are 2 key programs - a simple control loop known as RCA (read, control, actuate) that is controlled by MCL (Main Control Loop) and our ground station software.



  • Consists of reading sensor and valve data and storing the data in our registry


  • Reads data stored within the registry and checks for abnormal data.
  • If abnormal data is found, control sets a flag, which is a warning that something has gone wrong.


  • Actuate reads flags, and based on what went wrong, it actuates specific valves to resolve the issue(s).

Ground Station

The ground station can be thought of as a 'hub' on Earth that will communicate with our rocket 100km above the air! Ground station can actuate valves on the rocket, soft/hard abort in case anything goes wrong, receive live data pertaining to the rocket, request specific data from the rocket, and more. Currently, it does all this through web sockets over WiFi, but we will have to look into long-range communication methods in the future.


Results soon to come!

Live Stream

Livestream soon to come!


Look at some pictures of our hardware from our first attempt at a nitrous water cold flow!

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