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Please check my calculations for the exhaust velocity of a rocket that uses Nitrogen Tetroxide (N

##

V_e = \sqrt{{\frac{T*R}{M}}*{\frac{2*k}{k-1}}*[1-(P_e/P)^(^k^-^1^)^/^k] }

##

V

T = absolute temperature of inlet gas, K

R = Universal gas law constant = 8314.5 J/(kmol·K)

M = the gas molecular mass, kg/kmol (also known as the molecular weight)

k = c

c

c

P

P = absolute pressure of inlet gas, Pa

T = 3110 Kelvin

R = 8314.5

M = 20.24

k = 1.2314

P

P = 25 atm

[tex]

V_e = \sqrt{1,277,573.864 * 10.643 * 0.454}[/tex]

[tex]

V_e = \sqrt{6,173,137.26}

[/tex]

V

Are this calculations correct or did I make a mistake? I got the equation and most of the data from these two sites: http://en.wikipedia.org/wiki/Rocket_engine_nozzles, http://www.braeunig.us/space/problem.htm#1.10, and http://www.braeunig.us/space/comb-NA.htm.

_{2}H_{4}) & Aerozine 50 as its propelants. This is the formula that I'm using to find out the exhaust velocity:##

V_e = \sqrt{{\frac{T*R}{M}}*{\frac{2*k}{k-1}}*[1-(P_e/P)^(^k^-^1^)^/^k] }

##

V

_{e}= Exhaust velocity at nozzle exit, m/sT = absolute temperature of inlet gas, K

R = Universal gas law constant = 8314.5 J/(kmol·K)

M = the gas molecular mass, kg/kmol (also known as the molecular weight)

k = c

_{p}/ c_{v}= isentropic expansion factorc

_{p}= specific heat of the gas at constant pressurec

_{v}= specific heat of the gas at constant volumeP

_{e}= absolute pressure of exhaust gas at nozzle exit, PaP = absolute pressure of inlet gas, Pa

T = 3110 Kelvin

R = 8314.5

M = 20.24

k = 1.2314

P

_{e}= Pa = 1 atmP = 25 atm

[tex]

V_e = \sqrt{1,277,573.864 * 10.643 * 0.454}[/tex]

[tex]

V_e = \sqrt{6,173,137.26}

[/tex]

V

_{e}= 2,484.5799 meters per secondAre this calculations correct or did I make a mistake? I got the equation and most of the data from these two sites: http://en.wikipedia.org/wiki/Rocket_engine_nozzles, http://www.braeunig.us/space/problem.htm#1.10, and http://www.braeunig.us/space/comb-NA.htm.

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