Anything better than water ?

[FuSystems]

Hi again.

I just thought how you could more thrust with replacing the water.
When Actio=Reactio then "The heavier the fuel=the bigger the thrust" right?

The heavier the particles that you launch out of your rocket, the more power is needed for that.
And the more power you use to catapult them into the back, the more power will push your rocket into the front.
In theory--- plumb would be best, but its not available in such little balls (like sand) also its poisonous.
But.. Anything heavier than water.

And, because its launched out of your rocket within the first meters... it won´t make the rocket flying poorer. It will only increase your acceleration when starting. You use the air more effectively.

So, how about wet sand, or a sugar/water fuel?

Any Ideas ?


Fritz

[dongfang]

Hi,

This is one of the old unresolved problems ...

Consider:

- Denser reaction mass is also just heavier (to carry along for future reaction)
- Why not just add some more water if more mass is needed? OK you will need a bigger tank then, but water rocket tanks are pretty light, and extending one hardly affects air resistance either.

One of my own little theories is that an air/water mix is better than just water. I think it has a viscosity advantage over water, and it can expand during decompression, getting more speed. I have designed a mixer device and I am working on some flight logging gear to demonstrate a real performance improvement, but it's not yet ready. Anyway other rocketeers have improved performance with air/water mixes (as foam) so it's probably not totally crazy.

PS: An air/dry sand mixture could be cool!! Just for novelty. Or for winter use, where freezing water is a problem.

Regards
Soren

[RaZias]

In this forum I posted a tread about density, its a SCIENTIFICAL ARTICLE THAT STATS WATER WITH SUGAR GOES LESS HIGH (discussion closed lol)

[Andrewlee]

Talcum powder, baby powder, chalk powder. But for the most part, water is best because it does not compress.....well it does, but the amount in which is does is so minute, that it the best to be used for this application. If the water itself could be compressed, then you would loose the mechanical advantage you gain by shoving air on top of it.
The best way to put it, water rockets work like an internal combustion engine. The reason we make heavy duty pistons, is because if they were weaker, they would give in to the pressure (heat), thus taking away some of the mechanical advantage of the pressure pushing evenly over the entire surface . Now using water rockets, the solution to your problem of gaining more thrust, is to and more water, and to that same ration, add more air pressure and increase the volume for the pressure chamber, as well as make the length of your rocket longer. hence why so many of us prefer to use FLT rockets. See US Water Rockets.