[HEDM]

What do I do with that program by the way? Can you tell me step by step how do I add propep formulation?

Hydrazine is alright, the toxicity dosnt matter, its about the end products after combustion, hydrazine is one of the cleanest fuel. Hydrazine is used by the chinese launchers for over 100 times in the last decade due to its high density. Liquid hydrogen have a density of 0.07g/cm3, I believe we can find a better fuel than that.

As I already said.

"A 1% increase in specific impulse increases the ICBM range by 365 nautical miles (for a 5000 nautical miles ICBM) or more than 7%. A 5% specific impulse increase results in a nearly 45% range increase..."
-S. S. Penner, The Chemistry of Propellants: A Meeting Organised by the AGARD Combustion and Propulsion Panel.

Hydrazinium azide hydrazinate have a hydrogen density of 0.11, which is good enough for replacing liqui hydrazin. Aluminum hydride is also promising for a change. The cost is high for these materials, however I believe it is needed one day when you need to launch a whole space station. You're not going to expand the diameter of the rocket a lot, there is a mechanical limit of these materials, so the you need to make the fuel more efficient.

The price is worth it. When we start using the space much more regularly, we can afford it. Just like how people are willing to pay double price for premium seats on air travel, every second added to the propellant's efficiency can significantly increase the payload which is beneficial for launching a bigger piece of space station or space base. Liquid engines have a limit on its size, even the biggest liquid engine ever built produce thrust less than half of the side booster used by nasa's space shuttle launches.

Your idea probably fit best on linear aerospike engines. They can out-perform a normal engine by around 20-30%. Since liquid-mono-propellant is much less complex, it can utilize the advantage on linear aerospikes  since normal liquid engine have complex oxidizer fuel pumps around these smaller thrusters.

[Enthalpy]

I know hydrazine has been and is used, as well by Proton in big amounts. But everyone wants to go away from it, because the fuel's toxicity matters an awful lot, not just the exhaust. And again, density isn't so important at a launcher, that's why hydrogen is the very best of all fuels for performance. So much that Delta uses it at the first stage.

If not hydrogen, the natural choice is RP-1 or RG-1, usually called kerosene. Practically as efficient as hydrazine, but nontoxic and nonflammable, which changes everything at the launch operations and the induced cost.

Instead of Penner's claims, you could make your own opinion. By the way, 5% more specific impulse would be 15s over RP-1 for instance, and this would be a greater improvement than any dreamed fuel achieves - an excellent reason why designers stick at the safe RP-1. But the advantage of oxygen+rekosene over solids is 40s, that's why solids are disregarded.

To compare: the recent and much improved Vega has 3 solid stages plus a small liquid stage just to reach the Low-Earth-Orbit, while Falcon and Zenit reach the higher Geosynchronous Transfer Orbit with two liquid stages. This does make a cost difference. And two light hydrogen stages would reach the geosynchronous orbit directly.

Rocket designers don't pay so much attention to hydrogen fraction or nitrogen-to-carbon. What matters is (1) Safety (2) Practical operation (3) Specific impulse. Once (1) and (2) are fulfilled, the way your achieve (3) is your matter and doesn't result directly from such ratios. But for sure, solids won't compete with liquid oxygen.

Liquids don't need to push as strongly as solids, because a liquid launcher is so much lighter. Vega puts ridiculous 1.7% of its start mass on LEO, Falcon 2.6%, Delta IV M 3.8% thanks to hydrogen.

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Again, I have no desire to use a monopropellant as the main propellant. They are far too bad.
Only at the auxiliary flux that drives the turbopump.

The aerospike doesn't gain that much, and simpler methods are nearly as good.

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How to add compounds in Propellant.dat: look at the examples. Remember the units: cal/g and LB/in³.

Propep is historically an Ms-Dos programme (and even older than Dos supposedly), on which graphical interfaces were added. Mine is Cpropepshell found there (seems 404)
www.dark.dk/download
seems to be here now
http://users.cybercity.dk/~dko7904/cpropepshell/cpropepshell.htm
but others are good as well, like Guipep
http://www.lekstutis.com/Artie/PEP/
http://www.lekstutis.com/Artie/PEP/GuiPep.zip
http://www.ibiblio.org/pub/archives/rec.models.rockets/PROGRAMS

[HEDM]

I talked about hydrogen density and hydrogen content because hydrogen is the most desired exhaust a rocket propellant wants because it gives the highest performance. So the hydrogen count directly effect the specific impulse of a propellant. Again, you obvious can't just look at hydrogen, in my opinion NHO salts is perfect for solid propellants due to NHO compound's these characteristics. They can give very high hydrogen content, exhaust is totally gaseous, hydrogen bonding is extensive(Can you find a compound composed of only NHO atoms that does not have hydrogen bonding? none! or many few exceptions but none to my knowledge.), and it's energy content can vary(With HTPB, GAP, Aluminum powder, mixtures of these with NHO salts such as AN/ADN/HDN/HHDN/ can vary a lot, for example - Ammonium nitrate can give specific impulses around 150-220, ammoninium dinitramide can give specific impulses of around 240-320, hydrazininium dinitramide can push addition of another 5-10 seconds, and hydroxylammonium-hydroxylamine-dinitramide can give around 15 seconds more). To my knowledge, one of the best formulation to existent solid propellant can achieve an Isp of around 340-370, which is higher than Kerosene/LOX mixture, while having much higher density.

The density matters! The higher the density, the more fuel could be out into the same area, more potential thrust is carried. This means a rocket is able to fly higher with more fuel obviously, the reason why hydrogen is not used in many rockets is due to its very low density (0.07).

If polynitrogen materials are synthesized, which is possible (N5+ cation is synthesized, or 5,5'-bistetrazole or azo1,1'bistetrazole is chemically possible) These would have specific impulse of around 500-700, however their price will probably never make it to industrial production.

[HEDM]

btw, which propep did you download? my propep is just 1 single application, theres no other file i can extract or do anything to, such as editing.

[Enthalpy]

Your figures about the specific impulse are far off. 370s or 340s won't be achieved by solid propellants. Your sources are quite wrong, you can throw them away.

Density is widely uninteresting. I don't see what you mean by area. The effect is on the tank or casing mass; for a liquid, the tank mass is presently reasonable even with hydrogen, and for a solid, you can compensate the propellant volume by the chamber pressure to keep the casing mass, knowing that the pressure influences the specific impulse slowly. The thrust doesn't depend on it, whether at liquids or solids, whose grain shape can be adapted.

Hydrogen is used in engines. Explosion hazard is its drawback. Volume is an acceptable worry, cumbersome at pumps essentially. All other propellants are dense enough, nobody cares. Throw away all books that claim something else. Propellants are not explosives.

I use CPropepShell, but Guipep is widely equivalent. A single exe file must be an installer, which will create Propellant.dat among others, which you can modify. It demands much better accuracy than 100kJ/mol on the heat  of formation; 10cal/g accuracy isn't very good. A software estimate would be far too bad.

Yes, run Propep, and compare the propellants. You'll see that liquid oxygen outperforms any solid oxidizer (your numbers are off), and that all dense liquids are about as good as kerosene, hydrogen being the only one that brings significantly more specific impulse.

[Enthalpy]

I've tried Guipep again, and it's less useable. Propep alone is a DOS programme.
The best version I've had is CPropepShell, runes from W95 to Xp at least:
http://users.cybercity.dk/~dko7904/cpropepshell/cpropepshell.htm

[HEDM]

Your figures about the specific impulse are far off. 370s or 340s won't be achieved by solid propellants. Your sources are quite wrong, you can throw them away.

Density is widely uninteresting. I don't see what you mean by area. The effect is on the tank or casing mass; for a liquid, the tank mass is presently reasonable even with hydrogen, and for a solid, you can compensate the propellant volume by the chamber pressure to keep the casing mass, knowing that the pressure influences the specific impulse slowly. The thrust doesn't depend on it, whether at liquids or solids, whose grain shape can be adapted.

Hydrogen is used in engines. Explosion hazard is its drawback. Volume is an acceptable worry, cumbersome at pumps essentially. All other propellants are dense enough, nobody cares. Throw away all books that claim something else. Propellants are not explosives.

I use CPropepShell, but Guipep is widely equivalent. A single exe file must be an installer, which will create Propellant.dat among others, which you can modify. It demands much better accuracy than 100kJ/mol on the heat  of formation; 10cal/g accuracy isn't very good. A software estimate would be far too bad.

Yes, run Propep, and compare the propellants. You'll see that liquid oxygen outperforms any solid oxidizer (your numbers are off), and that all dense liquids are about as good as kerosene, hydrogen being the only one that brings significantly more specific impulse.

Solid propellants in the 300s is possible, these can be easily achieved by a huge list of exotic fuels such as berylium hydride and AP can give 310, aluminum hydride and ADN can give 298, etc. Recent advances on ADN formulation showed that 70%ADN 20%GAP and 10% Aluminum powder could give specific impulse of 327s, 3:1:1 of the same ingredients will give 335s, change it to aluminum hydride and it will be around 350, and if you change ADN to HNF it will punch another 5s. making it near 360s. Polynitrogen materials chould achieve as high as 500s. Density does matter obviously, would you rather choose a density of 1.1 or 1.5 if given the same specific impulse? Obviously 1.5 since more propellant mass could increase the payload by a lot. Wingborg et al. (2005) have reported specific/density impulse of ADN/water/fuel as being 10 per cent and 60 per cent higher than for hydrazine, respectively

http://cdn.intechopen.com/pdfs-wm/13473.pdf
http://arc.aiaa.org/doi/abs/10.2514/3.23911?journalCode=jpp
http://www.jatm.com.br/papers/vol1_n2/JATMv1n2_p153-160_ADN-The_new_oxidizer_around_the_corner_for_an_environmentally_friendly_smokeless_propellant.pdf

Ill try download the Cpropshell now.

[Enthalpy]

Yes, run CPropepshell, and check the figures. They are brutally wrong. If papers claim that, read different ones.

Density matters little because we can build tanks bigger.

[HEDM]

Yes, run CPropepshell, and check the figures. They are brutally wrong. If papers claim that, read different ones.

Here is the result. ADN is not in my ingredients so unfortunately I can use it, I used the another oxidizer of similar or slightly lower performance (HAN) instead of it and here is the results. Solid propellant based on ADN/HNF and AlH3 can out-efficient some of the most common liquid propellants such as O2/RP1 and N2O4/N2H4, BeH2 is there just to show what solids can do.



Of course, no solid propellant except polynitrogen materials can beat O2/H2 for now.

[Enthalpy]

You figures are wrong. To begin with, oxygen and kerosene outperform tetroxide and hydrazine, so the whole graphics is probably wrong. Bad proportions maybe. I can't imagine neither how to obtain only 300s from oxygen and hydrogen: engines get 420s even at a first stage, and 465s at a last stage.

Then, you should tell what are the pressures in the chamber and at the exhaust. Nor can you take the same chamber pressure for a solid, which translates into a heavy casing, and for liquids, which just take pumps. The RD-180 runs at 258 bar with light tanks, while the highest pressure I know for solids it 95 bar at Vega.

And of course, you shouldn't mention beryllium in any propellant, as this gives a very bad impression.

Even projected octaazacubane wouldn't beat oxygen and hydrogen, not even get near to it. It would outperform oxygen and cubane a little bit - if any useable - which exceed RP-1 by a dozen seconds.

[HEDM]

This is not my figures, its from PROPEP code as I already stated. APCP is not 190s, its in the 240s, and Hydrazine propellants are in the 300s. The PROPEP code under-estimate all propellant formulations by around 25%

Even projected octaazacubane wouldn't beat oxygen and hydrogen, not even get near to it.

Actually O2/H2 wont even get near to polynitrogen materials. polynitrogen materials will definately be much more efficient than O2/H2, first because polynitrogen materials is probably around 50 times more dense than H2, second, its specific impulse could achieve 500 easily.

http://link.springer.com/article/10.1007%2Fs10573-010-0020-x

The calculation is shown in this article, the high combustion temperature of polynitrogen materials could achieve nothing else ever could and therefore expand the gas very well.

The high density matters and is shown in this calculation.
http://www.sciencemadness.org/talk/viewthread.php?tid=29786

Normally small % increase in specific impulse can add much more % in payload or range. AlH3 can give around 10% more speicific impulse. However because Aluminum powder's density is 2.7 and aluminum hydride's density is only 1.4, the apogee of the calculated rocket's apogee only increased by 14% and the burn-out velocity by 8.2%

[Enthalpy]

Well then, you misuse Propep. It's accurate to better than 1%. Unsurprisingly, since many rockets have succeeded thanks to it.

All your results, all your claims are against experimental evidence, against well-established knowledge, against consensus.

One paper you cite gives a 200s range "estimate", that's nonsense, and relies on absolutely nothing. Worse, such compounds haven't been tried - nor even synthesized.

On the other link, you cite yourself. Congratulations. This won't convince me of anything, except that you should better search elsewhere the confirmation - or not - that your results make sense.

To be clear: all your results are wrong. Your figures, your assumptions, your claims.

I suggest that you first learn about rocketry, learn to use properly the software like CPropepShell, until you get some results that are compatible with the well-established ones, and only then, try to see if you may be right sometimes against the standard knowledge.

Don't hold to your wrong opinions.

[HEDM]

You clearly did not read the paper did you? They have shown the bond enthapies and why it could achieve such a high specific impulse. The combustion temperature could be as high as 5000.

I sited my self where I've sited many other sources, you should go read them. Do you have any sources which says hydrazine could out-perform formulations of ADN/HNF with an energetic binder such as GAP/NIMMO and an azide or hydride fuel such as AlH3 or N2H5N3?

[Enthalpy]

A computed heat of formation is worth zero. I don't need to read such a paper.

Any paper claiming 500s from nitrogen is meaningless, not worth reading.

You should distinguish between fiction and science among all these "papers", and between desired and possible.

[HEDM]

A computed heat of formation is worth zero. I don't need to read such a paper.

Any paper claiming 500s from nitrogen is meaningless, not worth reading.

You should distinguish between fiction and science among all these "papers", and between desired and possible.

Are you seriously saying heat of formation of polynitrogen compounds is worth zero? what do you use to calculate? toys like avorgrado? Have a look at this video then, how do you think it even explodes if nitrogenous compounds does not have positive heat of formation?

http://www.youtube.com/watch?v=Txa0fgIwiLA

This is azobistetrazole, N2(CN4)2