karol kerl

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since Jul 03, 2012
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Recent posts by karol kerl

Miles Flansburg wrote:karol,
so when the water goes through a rocket stove at a high temp, does it break down into O2 and H? And if so do they not add fuel to the mix?



One would have to mix wood dust with dust of some metals like aluminum or magnesium to get temperatures around 3000°C,
while offering something more attractive than hydrogen for marriage with oxigen.
Would destroy the RMH very fast.

Replacing a weaker bond by a stronger bond releases more energy as needed to break the weaker.
That's why something burns.
5 years ago

allen lumley wrote:
I am looking at a bottle of rubbing Alcohol that states it is 91% isopropyl by weight, by volume its closer to 70%!



It is the other way round.

Anyway.
In the best possible case the total content of water is 1/2 and 2/3 in the worst.
Thus the amount of latent heat, which could be recovered by condensation, is a lot higher as people may think.
5 years ago

allen lumley wrote:Karol Kerl : W.O.W., high school chemistry,and I ducked out and went to vocational school. Lets play the game, for every mole of Carbon we need 2 moles of Oxygen,
and we need 2 moles of Hydrogen for every Mole of Oxygen so most of the 'new molecule' arrangements are CO2, but not by weight ! once we think heavy thoughts -
Like where did I put THAT book we can figure out true proportions of CO2 and H2O by weight adding in the 10% at the end



Wood with an extremely high energy content.
Very raw calculation

Cellulose ~ 68.5%
C12H22O11 ~ 342.30 g/mol

Lignine ~ 28.5%
C10H12O3 ~ 180.20 g/mol

Terpene ~ 3%
C5H8 ~ 68.12g/mol


C822 H1507 O754
C685 H822 O205
C342 H548

C2H3O1 ~ 43.04

C2 ~ 24.02g ~ 55.80%
H2O ~ 18.02g ~ 41.86
H2 ~ 1.00g ~ 2.32

At 10 % moisture:
Carbon one pound
Water one pound

This Calculation was very sloppy.

A bit more precicely.
Cellulose ~ 63.5%
C12H22O11 ~ 342.30 g/mol

Lignine ~ 33.5%
C10H12O3 ~ 180.20 g/mol

Volatile ~ 3%
CH4

C23 H38 O14 ~ 538.5 g


C2 ~ 276.24g ~ 51.3%
H2O ~ 252.21g ~ 46.8%
H2 ~ 10.05g ~ 1.9%

At 10 % moisture:
Carbon 46%
Water 54%



5 years ago

Paul Ely wrote:
you have actually placed 9 pounds of wood and 1 pound of water.



No.
You have actualy placed about 4 pounds of carbon and about 6 pounds of water.

Wood is made up from long chains of sugar.
Ash neglected (1%).

C6H12O6 ~ 180.16 g/mol

C ~ 72.06g
H ~ 12.16g
O ~ 96.00g

C2 ~ 72.06g
H2O ~ 108.10g

At 10% moisture per kilo

Carbon 360g
Water 640g
5 years ago
I grew up in a two story house heated by air channels from a single fire place.
No fans, air only moved by heat.
The house was designed and build for this.
1500square foot floor space should be possible in such a way.
5 years ago
Low temperature/efficiency stirlings are quite simple to build,
however efficient stirlings are very demanding
as they need very high temperature differences.
5 years ago

malcom st. peter wrote:I found this http://www.superior-industries.com/dsf_5000_product_122.html.



Quite expensive stuff.

I was thinking of mixing it with copper powder, then packing it into a drum of sorts with copper tubing. I am thinking that this would make for greater surface aria for heat transfer.



It is not as simple as you may think.
One needs at least three sieve lines of the particles one wants to use in very precise ratios of size and weight
to get high thermal conductivity.

In this respect oil would do a far better job than grease, as one can put a lot more fine solids in a liquid with lower viscosity.
Even more if one heats it up before mixing.

You could try to get fin tubes for heat exchangers, which provide a lot more surface than standard tubes.
5 years ago

malcom st. peter wrote:Just wondering if anyone has thought about making there own high temp thermal conductive grease.



Hexagonal boron nitride.
(Sometimes called white graphite)
http://en.wikipedia.org/wiki/Boron_nitride

Can be mixed with high-temperature grease.

If this is to expensive for you,
then you may look at scientific papers about increasing thermal conductivity in polymers,
there are a lot on the net.
The principles can be used for grease too.
5 years ago

Dan Henn wrote:
I have used Hardi-Plank fiber-reinforced concrete siding on my house, the kind they sell at Lowe's and Home Depot, etc...



Standard concrete cannot withstand the high heat in a rocket.
You would need something based on refractory cement.
5 years ago