(Very) original hot air balloon photos

[Christophe]

A little bcp off topic but here are some beautiful hot air balloons:

https://www.econologie.info/share/partag ... fieres.pdf

ps: the energy balance of a hot air balloon must make it the most catastrophic transport in the world in CO2 / km. Passenger does anyone have figures in mind?

[Flytox]

Bonjour à tous

ps: the energy balance of a hot air balloon must make it the most catastrophic transport in the world in CO2 / km. Passenger does anyone have figures in mind?

Question energy "disaster", do not forget the rockets in their acceleration phase .... tens of tons of kerosene + oxygen burned in 2 or 3 minutes for barely a few hundred km traveled and a final useful weight of a few% of the original mass ..... A beautiful orgy of wasted energy.

Fortunately, the astronomical price limits drifts (except military satellites and paid space tourism projects)

A+

[Capt_Maloche]

In any case, it is superb to see, thank you

I found this on the autonomy of hot air balloons:

The duration of a flight depends on the outside temperature, the altitude, the weight of the passengers and the on-board gas reserves. A flight lasts an average of 1 hour.

The volume of current hot air balloons varies between 600 and 7 cubic meters, the most common being 000 cubic meters. This volume allows to carry a total load of around 2 kilograms, a cubic meter of air brought to 200 ° C can lift a load of 500 grams in normal ambient air and at normal pressure. The total mass of a balloon of 100 m250 is then of the order of 2 kilos, which represents significant inertia, and the whole art of piloting consists in anticipating the reactions of the aircraft. The autonomy depends of course on the gas reserves which one can embark on board the nacelle; the average flight time is around 200 minutes

I read on a site that 140 kg of gas had been necessary to travel 120 km in 2:30 at high altitude around 5000m.
Well that makes 56kg / h or 116 kg per 100 km !!

It's a fuel pit!
No wonder with the surface of the ball, inside at around 100 ° C

[Christophe]

Yes! Thank you for the details and the figures!

I thought it was energyvore but not to this point ... of the order of 150 L / 100 ... It is much more than a Formula 1 ... finally given the finesse of the canvas needed s 'wait ...

Was it a competition your numbers? Because 2h30 and 5000m is a lot, right?

ps: now I understand why all the "Montgolfiers" drive in a 4x4 or SUV ...

[camel1]

Hi everybody !

There is, as in many areas, an alternative to classic hot air balloons, the solar model ...

Go see there, it's exciting (and easy to achieve for those who are not afraid of anything! )

http://perso.orange.fr/ballonsolaire/index.htm

Energy balance: 0 g of CO2 emitted ...

Michel

[Christophe]

Super interesting but apparently it does not please everyone:

The solar balloon for human flight is grounded for regulatory and insurance reasons.

The captive and free flight tests stopped in 2003 because:
- there is no status in the DGAC boxes for aircraft adapted to the solar balloon ...!
- no air insurer wants to insure flights since it does not fit the boxes of the DGAC.

http://perso.orange.fr/ballonsolaire/reglementation.htm

[Capt_Maloche]

Was it a competition your numbers? Because 2h30 and 5000m is a lot, right?

ps: now I understand why all the "Montgolfiers" drive in a 4x4 or SUV ...

It was a walk above the Alps, at 5000m max the ambient temperature is still quite low; I don't know what was the average altitude

I suppose that at less than 1000m, consumption is lower

When at 20 ° C on the ground, it is -18 ° C at 5000m
Delta on the ground: 100-20 = 80 ° C
Delta at 5000m: 100- -18 = 118 ° C

Either consumption increased by 50% and surely more since the atmospheric pressure is only 0.5bar (+ 50% of volume)
C to d. around 2 times more than at low altitude

It must rather count in hours, because the average of a hot air balloon would be 30 to 40 km / h
They used 140 kg in 2h30, or 56 kg / h at an average altitude which I estimate at 2000m
They did an average of 48 km / h (thanks to the winds of altitudes)
On an average of 2000m, the average T ° is around 0 ° C
Or around a 20% surcharge

we can therefore count on 45 kg per hour for a traditional hot air balloon 3 or 4 places, WHAT MAKES 135 KG / 100 KM

Hi everybody !
the solar model ... go see there, it's exciting (and easy to make for those who are not afraid of anything! )

http://perso.orange.fr/ballonsolaire/index.htm
Michel

Yes, that's really super eco-friendly! and awesome too
What an economy! it makes me want to try with trash bags and a playmobile

but less beautiful than in your photos

[Christophe]

Mmmm for the consumption at high altitude I would not be sure: the cooler the air the denser it is and therefore the less it is necessary to heat the air in the balloon to obtain sufficient lift (Archimedes thrust). This parameter must therefore be taken into account in addition to the heat losses.

Balloon records are always made at high altitude is that it must be "positive" in the end ... in any case this is the case of the military explorer (who died last week by the way) who did around the world in a balloon.

ps: I love how the innocuous subjects a priori always deviate in econology (solar, energy ...)

[Capt_Maloche]

Have you finished telling C-ner-es?

at constant pressure the air is denser cold than hot.
At altitude the pressure decreases, so more volume is needed for the same lift, therefore more surface area of ​​hot air in contact with the ambient air, and the T ° also decreasing, there are more losses through the walls of the hot air balloon

If the balloons seek altitude, it is because there are fast winds, the Jet stream, up to 300 km / h
In this case, the yield per km becomes better ...

not that obvious aerology

PS: normal, this is the site that wants this

re PS: with a paramotor we consume 3 to 4l / h of fuel

re re PS: I know you don't see the rappo rt

[Christophe]

At altitude the pressure decreases, so more volume is needed for the same lift, therefore more surface area of ​​hot air in contact with the ambient air, and the T ° also decreasing, there are more losses through the walls of the hot air balloon

Well, it seems to me that in the water, the archimedes push does not depend on the depth, so no external pressure ... The only parameter is the difference in density between the volume and the environment. Am I wrong?

Oula it's old all this ...

Ah but it's different because water is incompressible (or almost) unlike air ...so the analogy doesn't work

Not obvious as you say