Good question. Probable one thin walled tank does cost less, as it can be made from two stamped halves wedded together.
And is more volumetrically efficient.
Yes, true for holding a liquid, like gasoline at near atmospheric pressure. It is only pressure tanks efficiencies that are independent (to first order) of the diameter because, unlike a low pressure tank, the wall thickness must increase with the pressure of the gas contained. This makes contained volume to wall volume (product of thickness and circumference) ratio a constant, neglecting end effects, which usually very slightly favor the smaller ID tanks.
A more importantly reason is fact that with a nearly empty tank, made of many small ID tubes, it would be difficult to get all the air out if filling it with an in compressible liquid, like gasoline.- I.e. you could not fully fill the multi-tube tank with gasoline.
With a vent at the top of each end that would be trivial.
It would need to be a very sophisticated valve that allows the air to escape but does not allow the gasoline fumes (and certainly not the gas one is trying to hold in the tank.) to escape. One way values are not very complex, but the discriminating exit valves you speak of/ are suggesting / need to sense and discriminate what is leaving (Gasoline vapors vs air) – Perhaps a small spectrometer as the detector could do this task?
The gasoline fuel pump would make a vacuum and collapse a gasoline tank into scrap metal without some vent. This vent lets air IN not gasoline fumes OUT. You don't dare put even only an air inlet vent in a gas storage tank. When filling a pressure tank with a compressible gas this is no problem - there would not be any vent as you need with a liquid fuel so the pressure steadily increases up to the liquifaction pressure.
Are you honestly saying here that you don't think gasoline tanks have vents?
No, I clearly said they have a simple “one way” valve that lets air into the tank but lets nothing go out. Read again the sentence of my post now bold.
I guess so as both you and adoucette* don't read with full comprehension what I ACTULLY say. Instead you both often think I said something I did not. This is for example why you asked me the above question even though I clearly not only said the gasoline tank has a valve but even told it was valve that let air in but not gasoline fumes out. ~60 or more years ago when there were less cars and people were not so aware of health damage caused by petro-chemical smog, I think the vents did let gas fumes, as well as air go out.
Another very common example of assuming something I never said is in next part of your post below. There are quite a few gases that could be stored (several even for use as a fuel) as liquid in pressure tank but you, I think, are assuming the tanks I have discussed (geometry and efficiency only) can only be used to hold gas like CH4. I will not bother to look up the pressure vs. temperature curve for gases that would liquefy at modest pressure but bet heptane and hexane would easily liquefy at modest pressure near room temperature. Again for what is about the 20th, time I have not specified any pressure or any particular gas. Assuming that I have and then being critical of me for your assumption is not fair. MY POSTS ARE ABOUT TANK GEOMETRIES & EFFICIENCIES, NOT SPECIFIC PRESSURES OR SPECIFIC FUELS unless asked to consider some particular pressure and gas as you did when concerned that the tank would explode if it held the 3600 psi which YOU suggested.
You can't liquefy room temperature natural gas by just adding it to a tank at 3000-4000psi. It won't liquefy. It may well liquefy at some pressure far beyond that, but that's going to require some very exotic tanks and materials - certainly not a bunch of welded together C's.
That is true for some gases (like CH4) and false for others (like C7H16, heptane, or some shorter hydrocarbon gases if heptane is already a liquid at room temperature and pressure).
Next you're going to post "but I never said I planned to put that particular pressure in my excellent flat tank!" even though that's the tank we're talking about. Whatever.
Yes. I see you have become aware that I am speak of the tank, not what it contains, but I admit the gaseous fuel (not the tank) most discussed in this thread is CH4 with only a few posts pointing out that there is much to be said for butane and some (but not me) think for H2 especially if tank is filled with a highly porous material to surface adsorb it.
When not forced to reply to / discuss / pressures or specific gases suggested by others, my posts have concerned two novel pressure tank types: One a set of many parallel small ID tubes & and the other many parallel rectangular cross section “tubes,” all but one sharing a common wall, which having no pressure across it does not “bow out.” – These common walls are really a “tension webs” between the two flat sides.
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*For another example in next post 1337,
adoucette assumes I must be speaking of fuel tanks, and yes that is one use but not the only use of tanks. Especially as at one point I did not know my multi-chambered, shared wall / tension web / tank was already for sale, I was thinking in term of a patent and trying to be as general as I could be - tanks have many uses other than as fuel tanks. It is really a sad waste of my time that at least half my posts must point out that I never said the thing I am be criticized for.
Adoucette's post are usually filled with unstated assumptions. For example that heptane can not be used as fuel as it has zero octane rating. - It works just fine in a Sterling engine - the most efficient engine that exist.
