[islandlabs] ignore these calculations (incomplete)

Burns, William burns at cshl.edu
Sat May 1 07:17:01 EDT 2010


Gas densities at 0C,101 kPa
Air Density 1.205
Hydrogen Density 0.0899
Helium Density 0.1786


Balloon Properties:
Model(g), Burst Dia(m), Cd
200, 3, 0.25
300, 3.78, 0.25
350, 4.12, 0.25
450, 4.72, 0.25
500, 4.99, 0.25
600, 6.02, 0.3
700, 6.53, 0.3
800, 7.00, 0.3
1000, 7.86, 0.3
1200, 8.63, 0.25
1500, 9.44, 0.25
2000, 10.54, 0.25
3000, 13.00, 0.25

*Balloon: 350
BurstDiameter(350)=4.12
*Launch diameter: 1.41373
*Payload (g): 150

Air_Denity_Model(?)=7238.3

Launch_Volume=4/3 * PI() * power(Launch_diameter/2,3)
Launch_Area=PI() * power(Launch_diameter/2,2)

Gross_Lift(Kg)=Launch_Volume*(Air_Density-Helium_Density)
Gross_Lift=Launch_Volume*1.0264

Free_Lift(Kg)=Gross_Lift-(Balloon_Weight+Payload_Weight)
Free_Lift(N)=Free_Lift(Kg)*9.81

Ascent_Rate(m/sec)=SQRT(Free_Lift(N)/(0.5*Balloon_Cd*Air_Density*Launch_
Area)

Burst_Volume=(4/3)*PI()*POWER(
Burst_Volume_Ratio=(Burst_Volume(cu m)/Launch_Volume)
Burst_Height(m)=Air_Density_Model*LN(1/Burst_Volume_Ratio)



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