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Add formatting, and explicit units, add tags.
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edit approved May 30, 2022 at 23:03
No Nonsense
edit approved May 30, 2022 at 23:03
No Nonsense
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I'm quite sure this is either a small or just plain stupid mistake but my anxiety is getting the better of me. when calculating exhaust velocity this is the equation used:

enter image description here

however I keep getting higher values than that listed, specifically on Astronautix. I should mention I am solving for monopropmonopropellant HTP-85%, where M = 20.7$M = 20.7 kg$, k = 1.34$k = 1.34$, Pc = 10 bar$P_c = 10\ bar$, Pe = 1 bar$P_e = 1\ bar$, Tc = 910k$T_c = 910\ K$ and R$R$ is the universal gas constant. I suspect that it is just the difference between theoretical and actual performance however 1128ms^-1$1128\ m \cdot s^{-1}$ is very different from ~900ms^-1$~900\ m \cdot s^{-1}$. Is there something I am missing or am I just using the formula in the wrong context?

I'm quite sure this is either a small or just plain stupid mistake but my anxiety is getting the better of me. when calculating exhaust velocity this is the equation used:

enter image description here

however I keep getting higher values than that listed, specifically on Astronautix. I should mention I am solving for monoprop HTP-85%, where M = 20.7, k = 1.34, Pc = 10 bar, Pe = 1 bar, Tc = 910k and R is universal gas constant. I suspect that it is just the difference between theoretical and actual performance however 1128ms^-1 is very different from ~900ms^-1. Is there something I am missing or am I just using the formula in the wrong context?

I'm quite sure this is either a small or just plain stupid mistake but my anxiety is getting the better of me. when calculating exhaust velocity this is the equation used:

enter image description here

however I keep getting higher values than that listed, specifically on Astronautix. I should mention I am solving for monopropellant HTP-85%, where $M = 20.7 kg$, $k = 1.34$, $P_c = 10\ bar$, $P_e = 1\ bar$, $T_c = 910\ K$ and $R$ is the universal gas constant. I suspect that it is just the difference between theoretical and actual performance however $1128\ m \cdot s^{-1}$ is very different from $~900\ m \cdot s^{-1}$. Is there something I am missing or am I just using the formula in the wrong context?

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R. Hall
R. Hall
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Inconsistencies in calculating exhaust velocity

I'm quite sure this is either a small or just plain stupid mistake but my anxiety is getting the better of me. when calculating exhaust velocity this is the equation used:

enter image description here

however I keep getting higher values than that listed, specifically on Astronautix. I should mention I am solving for monoprop HTP-85%, where M = 20.7, k = 1.34, Pc = 10 bar, Pe = 1 bar, Tc = 910k and R is universal gas constant. I suspect that it is just the difference between theoretical and actual performance however 1128ms^-1 is very different from ~900ms^-1. Is there something I am missing or am I just using the formula in the wrong context?