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10/27

Updated specifications:

Specification	Value
Contraction Area Ratio	8.085
Chamber Diameter	3.25 in (min)
Throat Diameter	1.143 in (min)
Characteristic Length	63 in
Chamber Length	6 in
Contraction Angle	30 deg
Expansion Angle	15 deg
Exit Diameter	2.576 in
Exit Pressure	14.12 psi
Chamber Pressure	460 psi
Mass Flow	1.22 kg/s
Exit Mach Number	2.723

Contraction ratio issue solved. Now have chosen maximum acceptable value of 10
Exit pressure is 97329.71 Pa, ideal calculations, see if matches RPA
nozzle sized 1.5 mm less to account for expected 0.1 mm/s erosion
exit area also sized down to match nozzle (with slight round up)

To do:

Thermal analysis
Graphite and phenolic erosion modeling
O-ring sizing
Slides

References:

https://ocw.mit.edu/courses/16-512-rocket-propulsion-fall-2005/resources/lecture_3/ (Exit pressure)

https://www.eucass.eu/doi/EUCASS2017-474.pdf (L*, contraction ratio)

https://ntrs.nasa.gov/api/citations/19710019929/downloads/19710019929.pdf (angles, general)

https://yang.gatech.edu/publications/Journal/JPP%20(2008,%20Thakre).pdf(graphite)