Characterizing SF propellant part 2

Additional tests were performed on August 15th,2020 on the SF propellant.

The 3 additional tests were performed with the following changes:

Graphite nozzles replaced plastic nozzle
Grains were accurately weighed prior to each firing
Pressure transducer piping was completely packed with high temperature lithium grease.

Run 1: 21/64 throat straight nozzle

Pressure vs. Time data

Pressure Data 21/64" throat

Force vs time data

Force Data 21/64" throat

Results:

Peak pressure 1026 PSI +- 8PSI
Average Pressure 816 PSI +- 7 PSI
Peak Force 95.5 lb +- 3 lbs
Average Force 75 lb +- 3 lbs
Burn time: 2s +- .1 s

Run 2: 22/64 throat straight nozzle

Pressure vs. Time data

Pressure Data 22/64" throat

Force vs time data

Force Data 22/64" throat

Results:

Peak pressure 886 PSI +- 7PSI
Average Pressure 638 PSI +- 7 PSI
Peak Force 88.4 lb +- 3 lbs
Average Force 64 lb +- 3 lbs
Burn time: 2.3s +- .1 s

Run 3: 23/64 throat straight nozzle

Pressure vs. Time data

Pressure Data 23/64" throat

Force vs time data

Force Data 23/64" throat

Results:

Peak pressure 691 PSI +- 6PSI
Average Pressure 543 PSI +- 5 PSI
Peak Force 79 lb +- 3 lbs
Average Force 61 lb +- 3 lbs
Burn time: 2.4s +- .1 s

Comments

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