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Nozzles are responsible for accelerating the flow of gasses. The come in a variety of flavors, including DeLaval Nozzles and Aerospike Nozzles. The team typically manufactuers its nozzles from isomolded graphite turned on a lathe.
Materials
The team has traditionally used graphite for our nozzles. In the past we've used Superfine Isomolded graphite for it's superior mechanical properties, however after discussion on TRF, it was noted that lower grade graphites perform better. At the suggestion of "The Graphite Store" the team is currently evaluating pullstruded "Fine" graphite of grade GR030.
The full assembly also uses an phenolic round the graphite sits in and an aluminum carrier that the phenolic sits in. The phenolic is rtv'd into the aluminum carrier which provides a interface for the assembly to be bolted to the case.
Examples
The team has built a variety of nozzles in various sizes over the years. Known examples are linked belowCharacterization Nozzle #3
| Nozzle | Outer Diameter | Throat | Fate |
|---|---|---|---|
| All American Nozzle | 54mm |
| 13 x 54mm |
| firings. Flew on Zach B's All American at MDRA August 2016. Survives in lab | |
| 1G Z-Nozzle | 98mm |
Cracked during Characterization Static Fire #2, previously survived 6 98mm |
firings. | |
| 4G Z-Nozzle | 98mm |
Undetected Stress Concentrator broke the nozzle during XB-98-4G #1 | ||
| 4G Z-Nozzle Rev 2 | 98mm |
| New design survived RUD of XB-98-4G #2 and successfully |
| fired during XB-98-4G #3 and OW-98-FIN1, broken during removal from case after finocyl test | |||
| Characterization Nozzle #1 | 3.62 in | .42 in | Destroyed during Characterization Static Fire #1 |
| Characterization Nozzle #2 | 3.62 in | .42 in | Survives in lab. Unused, will probably RUD if you use it. |
| Characterization Nozzle #3 | 3.62 in | .48 | An angry lathe ate this nozzle when it was parted off. A little dinged on the edges. |
| Characterization Nozzle #4 | 3.62 in | .5 in | No diverging section. Used for Characterization Static Fire #5 |
| 152mm Nozzle Insert #1 | 5.01 in | 1.357 in | Successfully fired in OW-152-4G #1 but cracked after firing, rendering it unusable for future tests |
| 152mm Nozzle Insert #2 | 5.01 in | 1.150 in | Successfully fired in OW-152-4G #2 |
| 152mm Nozzle Insert #3 | 5.01 in | 1.655 in | Fired on OW-152-8G #1. Failed axially at T+2.9s |
| 152mm Nozzle Insert #4 | Fired on OW-152-8G #2 | ||
| 152mm Nozzle Insert #5 | Flown on Hermes Flight 1 | ||
| Medusa Nozzles | Being used in the experimental P-Motor. Yet to be fired | ||
| Prometheus Booster Bell | 2.859 in | 1.15 in | Successfully CNC turned. Static Fired and Flown at test launch. New Isomolded graphite seems reusable (needs to be tested) |
| Prometheus Sustainer | 2.261 in | 1.15in | not fired nor flown. |