Extremely Bad Report On Air Powered Cars
November 1st, 2009
|
| Share |
If you know anything about pneumatics, mechanics, physics or any number of other disciplines, you probably can see a lot of problems with the idea of powering a car with compressed air. Sure, it *can* be done, and nobody will doubt that, as compressed air vehicles have been around a long time. At one time, compressed air locomotives were used to haul carts in mines and factories, where steam engines were not an option. They fell out of favor when electricity became an option, because, when it comes down to it, compressed air is a lousy way of storing energy.
When you compress air, it gets hot. For this reason compressors generally have a fan to keep them from overheating. The heat is mostly lost in the compression process and when the air expands again, it comes out very cold. This cold air does not expand very much, so most of the energy is lost. One way of attempting to increase the energy output is to try to send the air through some kind of heat exchanger to bring it back to the ambient temperature. This may help a little, as long as it’s not cold out to begin with. If it happens to be a cold winter day, then you’re going to need to heat that air with some kind of flame or heating element, just to get it to work decently – that, of course, defeats the whole purpose.
In addition to this, both compressors and pneumatic engines tend to be extremely inefficient. The energy density of compressed air is pitiful and to actually get it to have any chance of holding a reasonable amount of energy it needs to be compressed to the extreme. This is not only very inefficient, it’s also downright dangerous. If you breach a gasoline tank, the gasoline will trickle out. It usually will not catch fire, as gasoline is surprisingly difficult to ignite in the liquid phase (deisel is even more difficult). If it does catch fire, it will burn, but contrary to what you might see in the movies, it will not explode – for that, it needs to be vaporized and mixed with air. However, any breach of tank of highly compressed air will result in an explosive release of the energy it contains. A single SCUBA tank explosion can take out the better part of a dive shop, so if you happen to get into an accident with a compressed air-powered car, you won’t even have enough time to say “Smile you son of a…” before being pulverized by the air tanks.
One might think that any favorable report on this extremely poorly planned technology would be bad, but this one adds an extra measure of idiocy. Just wait until you get to the end part of the segment around the three minute mark.…
Yeah, you heard right. “Perpetual motion.” Somehow nobody from the narrator to the writers to the production assistants saw the obvious problem with this idea – or maybe they just didn’t care enough to point it out.
This entry was posted on Sunday, November 1st, 2009 at 10:18 pm and is filed under Bad Science, Enviornment, Just LAME, Not Even Wrong, Obfuscation. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
View blog reactions
November 1st, 2009 at 11:01 pm
I had this same debate with someone a year or so ago – he just couldn’t seem to understand that while gasoline may burn and can be an explosion waiting to happen, compressed air is an explosion which is *actually happening right now* and is being contained by a thick metal container.
That stuff is dangerous – the father of a friend of mine is a high school chem teacher, and he told us about an accident with one of the cylinders in the lab (I want to say H2, but it could have been O2). The end snapped off, and like the bottle rocket it had just turned into, the thing punched through 2 walls befor it embedded itself in a 3rd. And this is what they want riding under me? I’ll go with an internal combustion engine, thanks.
Those number claims (speed, range) are interesting – I would *love* to see him try to show that
And perpetual motion????? My brain wants to melt.
Quote Comment
November 1st, 2009 at 11:34 pm
Matthew said:
Yeah, I am extremely skeptical of that. Granted, the car is extremely light weight and is packed end to end with air tanks, but still, 200 miles?
I did some research on this and found some interesting info: there are designs for compressed air augmented cars, that would be sold as “air hybirds” and would feed the compressed air to internal combustion engines that are supposed to have ranges of something like 200-300 miles, but that’s really deceptive, since they’re actually super light weight ICE powered cars for the most part.
The ones shown on the video are supposed to have a range of 80km. They say that they plan on going further, but right now, their design range is 80km. Nobody has actually driven one that far as of yet, but that would be the theoretical range. Of course, that’s not the range when driving fast – that is the range under ideal conditions. In other words, driving at low speed on a level surface on a hot day.
Also, as far as things are now, these could not be imported to or sold in the US and possibly could not be sold in many European countries either. They don’t meet passenger car safety standards for crashes. Not only the air tanks, but they are super-light to the point of being extremely flimsy. Their sales would depend largely on countries where they could be registered as something other than an automobile. They would be registered as something equivalent to a golf cart or something – a vehicle that would not need to meet automobile safety standards.
Quote Comment
November 2nd, 2009 at 1:19 am
Well yeah, you always get the rosy picture bull**** from this, but when they started talking about an air powered generator that powers the compressor and then said it would be perfect perpetual motion with no need to fill, I think I flet a part of me die. That’s the stupidest thing I’ve heard in a while.
Quote Comment
November 2nd, 2009 at 1:44 am
My take on this:
Remember this is a car that first being built in and for INDIA.
1-Yes a lot of energy is lost to compress the air and then when it expands. So what? This makes it just like a battery, which also have some pretty terrible energy conversion rates. The only difference is that it can be charged quicly from a large compressed air tank. Compressed air filling stations are an option.
2-Yes it’s flimsy and without safety features, but it’s being built for India and they don’t expect too many safety features.
3-The fact that air cools as it expands means FREE air con which is a big plus in INDIA where it’s damn hot dontcha know.
4-The tanks have pre-cut weak points on the undersides so that if there’s a tank rupture it will explode downwards. It’s no more dangerous than riding around with 50l of highly flammable petroleum.
All in all, I think this is a great small, cheap, urban car for India, but trying to bring it over to Europe or the US takes the kind of idiocy and lack of scientific eduction that is expressed by the people who made that video.
Quote Comment
November 2nd, 2009 at 5:27 am
metatron said:
I can’t watch the video because there’s no flash here, but I’d hazard a guess that, amongst other things, this is being touted as energy efficient or using renewable energy (or even being a perpetual motion machine, which is the extreme to which ‘renewable energy’ attempts to lead, but the less said about that the better).
metatron said:
So because they’re poor they don’t deserve safety features.
metatron said:
Wonderful. So if there’s a problem it turns into a plane. Of sorts. Except that there’s this gravity thing to account for dontcha know.
metatron said:
It’s a stupid idea no matter where it is. Just because people live in another country and/or are brown does not mean they don’t deserve the standard of life we enjoy.
Quote Comment
November 2nd, 2009 at 11:59 am
When a valve is knocked off a compressed gas cylinder it is bad enough: http://www.youtube.com/watch?v=tyINNUaXa8Q
A breached cylinder wall would be absolutely catastrophic, and the size of those tanks in the car are a bit scary!
Quote Comment
November 2nd, 2009 at 12:14 pm
My dad told a story of an oxygen cylinder that got loose at the hospital. Went through several walls, but fortunately did not start a fire or hurt anybody.
I tend to regard compressed-air cars as a cool engineering trick and maybe a fun little toy, but not much more. I admit the technology is starting to get to where it might actually be practical, providing people can get their cylinders recharged, but it still seems more like a toy than a real car to me.
Quote Comment
November 2nd, 2009 at 1:18 pm
metatron said:
Translation – The technology sucks. It would never work out in a country where people were accustomed to decently safe and usable vehicles, but it might work in a country which has a low enough standard to begin with.
metatron said:
Actually, batteries are very effecient in terms of energy conversion. Lithium ion batteries can be as high as 98% and even lower tech batteries are usually better than 75%. I’m not entirely sure about the air conditioning aspects. I suppose you could circulate air around the tanks, but that might make it too heavy. releasing the air into the cabin might not be such a great idea. It would be noisy to say the least.
metatron said:
Again, I’m not so sure that this proves anything other than the thing is so unsafe that it would only be acceptable in places with really lax safety standards. Really though, I don’t think it’s justifiable to go with that. The lives of indians are just as worthwhile and so writing them off as acceptable seems cruel and a little racist.
metatron said:
Actually, gas tanks almost never explode and rarely catch fire. That’s what is great about petroleum fuels. They’re surprisingly difficult to ignite when confined and in liquid form. Mythbusters did something where they tried to make a car explode by shooting the gas tank and shooting it with tracer rounds and blowing it up etc etc. It never really did much except trickle out. They also found that a standing pool of gasoline will burn, but not explode and it’s easy to go out. Diesel you can’t get to burn in a standing pool, even if you drop a match in it!
Anyway, pre-cut weak points can only do so much. An air cylinder can’t fail in a non-catastrophic manner. It either explodes BOOM or it takes off like a rocket. Take your pick, both are really bad. Even if the shrapnel does not get you, the release of pressure can rupture ear drums of everyone near it. If it ruptures on the bottom it will likely hurl the car into the air.
metatron said:
Note that the video does not tout it as a cheap short-haul lightweight transit method for inida. They portray it as the next big thing in transportation and also as a perpetual motion machine
Quote Comment
November 2nd, 2009 at 3:35 pm
Engineering Edgar said:
That’s precisely what I said.
I didn’t get my information from the video, i googled it. I still think that this thing will have a niche market in India, but the people who made that video are total morons.
Quote Comment
November 2nd, 2009 at 7:00 pm
Compressed air as an energy carrier has several advantages; powertools run cooler, they are lighter than their electric counterparts for the same amount of delivered energy, and for rotating tools – run at higher RPM. The one thing it is not is cheap. Any one that runs a workshop of any decent size will tell you that compressed air is the most expensive energy they pay for, and the idea that it could be used to power a car economically simply ridiculous on its face.
Added to this the performance that is being claimed for these vehicles is outright impossible, as a few moments with a pencil and paper will show, nevermind the ludicrous suggestion of perpetual motion.
Quote Comment
November 2nd, 2009 at 9:01 pm
Of course, pneumatics have big advantages when it comes to a number of applications that require compact, light devices and high forces. A compressor can build up pressure in a chamber and then release it quickly, which is great for something like a nail gun, which would be difficult to do with electricity – you’d need a big solenoid to give that kind of impact and it would likely exceed the peak power a source could provide, so you’d need to have capacitors to discharge – pneumatics work better for that. Of course the same is true with impact wrenches and jack hammers.
high power, high RPM, devices like dental drills and such things also work well with pneumatics. Pneumatic actuators and light weight and rugged.
But it’s horrible for storage.. even if it has some good nitch applications for tools and such.
Quote Comment
November 3rd, 2009 at 3:27 pm
Heh — I’m suddenly reminded of when Red Green (of “The Red Green Show”) tried to build a wind-powered boat. Harold immediately pointed out that a wind-powered boat is a sailboat, but Red clarified that sailboats are for sissies; they wanted something that was green and *manly*. So they were going to put a wind turbine on the boat to power an electric motor which would drive a propeller, all held together with the handyman’s secret weapon, duct tape. It was, of course, disastrous.
Quote Comment
November 4th, 2009 at 8:32 pm
Yeoz said:
This isn’t related at all, but it is _neat_: http://www.youtube.com/watch?v=JtuWxr7Djjo
It’s containers full of various kinds of commercial fireworks being blown up to test the effects. The 75 mm colour shells and the waterfalls was jaw dropping.
Quote Comment
November 7th, 2009 at 12:51 am
metatron said:
The fact that this sounded logical in your head makes me want to cry a little. When you compress the air into the tank in the first place IT GETS REALLY HOT. A very large part of the energy used to compress air is wasted by generating heat.
So any heat absorbed by the tank while you are using the air is going to be less than the heat that was generated in the first place when you filled it, unless the second law of thermodynamics suddenly ceased to be true at some point.
Quote Comment
November 19th, 2009 at 1:25 am
The car will go over 60 miles in a day if you don’t go over 35 and if you are going any further than that you are likely to get on the highway. Everyone will just have to plug in your car at night just like you would your cell phone. I don’t see myself ever having to fuel at a gas station. An 800 mile range is more than most Americans can drive at a single time. Do the math if you drive 70 miles an hour for 10 hours (which is a lot) you will only get to 700 miles. After 700 miles of driving what do you do? Sleep. If you’re at a hotel I am sure you could find a way to plug in your car. Then in the morning a quick trip to the gas station and your are ready for another 800 mile road trip. People in general will have to plan ahead. Geez, we did it before the advent of the cell phone. You plan your day out. Then let someone know when and where you will be. Who cares if its ugly? If you buy this car it’s not for the look. It is for the utility of the car, which is what everyone should consider when purchasing a car, a house, or anything.
Quote Comment
January 8th, 2010 at 1:42 pm
Hi,
I thought that all you guys would be able to know difference between a journalist effect and the device they try to show you : “perpetual motion” that is mentioned at the end of this video is a communication trick and was never mentioned by inventors of this compressed air car concept.
For serious reference, you should see official web site :
http://www.mdi.lu/english/
The first car is in test at Amsterdam airport :
http://www.youtube.com/watch?v=XT1sVKUlOYA
The intent of current version is not to replace long range cars, it is only to be very efficient for city traffic : small, robust, light and cheap. And first version is very convenient on airport as there is no safety danger as electricity or fuel for aircraft refueling.
As you may know, all current internal combustion engine are compressed air engine : what is pushing piston if not gaz pressure ?
But pressure is obtained by burning something, to obtain heat then pressure.
The simple idea from Mr Negre is to separate burning stage and decompression stage.
One advantage is that keeping pressurized air is 100% efficient and very cheap.
Other advantage is that engine is far more efficient, because each cylinder is making torque at every single rotation with full strength, instead of internal combustion that have one rotation for compressing fuel mix, and next rotation only to push and make torque, half of it being used for compressing next cylinder.
For those that say that compressing air is not efficient, they seem to ignore that this is what is done on all internal combustion engine in a very extremly inefficient way, because they have to do it too fast (more than 3000 or 4000 times per second…).
If you take time to do it, at home, it can be lot more efficient, either :
- mechanically, and then you can use heat for your home ;
- by thermal process, and surprinsingly very efficiently by cooling instead of heating…
But think about it instead of shouting away…
Quote Comment
January 8th, 2010 at 2:22 pm
brnd said:
It is not effecient at all. Robust? I’m not sure how you would define that. If you’re stuck in a part of the city that isn’t near a big compressor station, it’s not going to be robust at all. As for cheap? Granted, the capital cost of this may be low, but you get what you pay for.
These vehicles would not be permitted to be registered for use on public roads in North America or most European countries. They don’t meet even the most basic safety standards. In fact, they don’t even come close.
brnd said:
I feel a lot safer riding on a pile of batteries than a compressed air tank. There’s basically no way that the tank can fail that isn’t going to be extremely catastrophic. Of course, the vehicle does not eliminate electricity, as there still needs to be electricity to power the lights, turn indicators, instrument display and such accessories like that.
Not that there’s any danger to begin with from electricity for fueling an aircraft. Jet-A has a low vapor pressure, high flash point and is pretty stable in general. It’s offloaded from trucks with electric components onto an aircraft by guys who are using flashlights and talking on radios all the time.
brnd said:
It is nowhere near 100% effecient, even under the best conditions and under normal conditions it’s one of the least effecient ways of storing energy.
brnd said:
Internal combustion engines are thermal engines. A gasoline ICE can achieve a good 30% effeciency under normal conditions and even more if it is operated at it’s optimal RPM and has features like a turbocharger. High compression diesel engines can go well beyond 40% thermal effeciency. This is excellent by any standard.
brnd said:
You’re basically saying that despite being extremely ineffecient that there may be some narrow circumstances where some of the losses can be recouped by waste heat recovery.
Quote Comment
January 10th, 2010 at 8:17 pm
drbuzz0 said:
In urban cycle, moving 1t car for transportation of 80kg of human is not efficient at all, sure.
And moving 300kg for transportation of 80KG of human is almost 3 times more efficient. This is the goal of compressed air car.
drbuzz0 said:
Lets just say that MTBF will be long, as all that fail often is removed…
drbuzz0 said:
Yes, sure, just try to tell me that you really think that the meaning of “robust” has to do with the number of refueling points…
The target of the first version is for internal use of some large companies, or for renting cars. The idea is to adapt the concept of free bicycle renting that is a huge success in Europe for public transportation. Refueling is part of float management.
drbuzz0 said:
Fair, this is all what i would need.
For the same price, you may only pay a third of the batteries for an electric car, with life end less than 4 years, so you don’t even get what you pay for…
drbuzz0 said:
You don’t even know what you talk about…
Composite materials are far more resistant that any metal equivalent nowadays. Ask to F1 pilots how their life cell is made.
drbuzz0 said:
So ask why many laptop companies had to recall all batteries… Exploding batteries when rated power or temperature are exceeded is quite difficult to handle…
drbuzz0 said:
Sure, and this is why firemen takes same tanks on their back with same pressure when they enter buildings in fire… Life of tanks is more than 12000 reloading cycles, only 32 years for one reloading per day, and 18 Millions of Km at 150km per reload.
Just try that with any batteries…
drbuzz0 said:
Yes, sure, i may just tell you that LEDs has been quite useful for cars now… And you don’t need any batteries to start the engine.
In fact, when anyone wants to be sure that a diesel generator will start, they use… compressed air.
drbuzz0 said:
You seems to know things better that aircraft companies. Like the meaning of “robust” word ?
drbuzz0 said:
Yes, sure, this is why a german company prefer to use compressed air than batteries to store production of their windmills…
drbuzz0 said:
Yes, sure, try to heat a ICE and wait to see it turning…
This is gaz pressure that push piston, all piston engine are compressed air engine.
But on ICE, you have to spend 1 rotation to prepare and burn the gazoline/oil/gaz, and another rotation to have the pressurized air push the piston, while using half pressure to pressurize the next cylinder…
In pure compressed air piston engine, without internal combustion, pressure is pushing every single rotation at full strength.
drbuzz0 said:
This is clearly better that any existing nuclear plant. But turbocharger are no more compatible with pollution standards.
Then these dreamed efficiency are posible on generators with stable speed, not with engine in urban cycle.
And engine efficiency is not at all car efficiency : if you need more than 1000kg to transport 80kg, you are close to 7,4% efficiency. Can you just tell me what is mean weight of running cars in the USA today ?
drbuzz0 said:
Why are you using your intelligence in such a perverse attitude ?
You say on one side about a 40% efficiency that
drbuzz0 said:
and for mechanical compression with efficiency more than 60%, this is “extremely ineffecient” ?
As i told you, it would be more efficient to use thermal compression like in the ICE… If this is excellent inside ICE, why would it be less than excellent at home ?
Quote Comment
January 10th, 2010 at 8:57 pm
Compressed air as an energy carrier is an old and well understood technology. It is used constantly in shops because power tools that run on compressed air are lighter, run cooler, and done sustain damage in a stall, than electric power tools.
But the one thing compressed air is not is efficient. It is well known to be the most expensive form of energy in any industrial shop. The truth of this can be found via any search in Google. Any idea that has compressed air used as motive power in any transportation medium will by necessity be forced to assume this low efficiency; there is no way to avoid it.
Those that back this as a solution to transport only demonstrate a deep ignorance of basic physics, and fundamental engineering principles.
Quote Comment
January 11th, 2010 at 5:16 am
Hi,
DV82XL said:
So we can agree that the decompression stage is very efficient and powerful.
Running cooler is a great natural advantage, both for mechanical behaviour of materials, and for performance : it means that by using low temperature heat, coming from environnement, from solar concentration or from very efficient continuous combustion (95+ efficiency), compressed air engine can absorb thermal power to give more mechanical power.
You have in fact more a natural heat pump than a typical ICE, where excess heat is lost.
DV82XL said:
Do you mean that the compression stage is not efficient ?
Because storage stage for compressed air is the most efficient storage of mechanical energy i know, as there is NO LOSS at all. You can keep compressed air for years in a tank, without losing any energy. And tank can be very simple, like a hole in the ground and some concrete to make very solid tank.
Quote Comment
January 11th, 2010 at 7:36 am
brnd said:
Thinking you can ignore the laws of thermodynamics because you find them inconvenient is one of the signs of a crank.
When you demonstrate some grasp of physics, we can continue this conversation.
Quote Comment
January 11th, 2010 at 8:03 am
DV82XL said:
Are you always insulting people when physics evidences are against your ideas ?
I gave you many facts and figures about decompression stage, storage stage and compression stage.
You agree that decompression stage is efficient and create cold temperature.
You may agree that storage of compressed air is 100% efficient, with no loss at all.
You don’t seem to agree that compression stage is efficient enough, at a minimum of 60% efficiency.
Compression is the basis of all “heat pumps”, and they have the highest Coefficient of Performance we know in industry.
What can i say more ?
What is wrong in what i said ?
I wish you to be able to cope with your emotions…
Quote Comment
January 11th, 2010 at 10:48 am
brnd – You don’t know what you are talking about, it is that simple. Most of your ‘facts’ are wrong or wrongly stated.
Decompression of compressed air, and its storage is not something that can be described as ‘efficient’ to begin with, that parameter does not apply in these instances. Cold is never created as much as heat must be supplied from outside the system, as waste heat must be sunk when compressing it, that in and of itself are counted as thermodynamic losses. Storage, in this the case of compressed air may be loss less, (although in my experience this is never so) but the term ‘efficient’ does not apply unless you are comparing it with some other medium on a power-to-weight ratio or something similar.
Heat pumps move heat, that is their function, that makes them perforce poor at storing energy in the compressed gas they use as a carrier. Not only are heat pumps not applicable to your argument, to they are, they undermine it.
To recap: Efficiency is a measurement that must compare an output to an input, one cannot talk meaningfully about the efficiency of the various stages in this type of system independently. Second moving heat and storing energy are diametrically opposed functions of this type of system – the better it is at one, the worse it must be at the other.
Spend some time to study the Idea Gas Law and the three Laws of thermodynamics. You obviously have no idea what you are talking about, and that too is a clear statement of fact.
Quote Comment
January 11th, 2010 at 7:50 pm
DV82XL said:
Sure, it is always easier to attack people than hard facts.
DV82XL said:
Please don’t dilute and mix things in foggy words. Just quote my sentences one by one and tell me what is wrong, i really need to learn from you.
DV82XL said:
Are you explaining me that you cannot find a way to compute the efficiency of a storage, nor the efficiency of a compressed air engine, nor efficiency of a car ?
If you can, you should teach me by showing me some formula…
DV82XL said:
I need more explanations on your sentence…. Any explanation about “cold creation” would be nice, for instance.
DV82XL said:
I will try to explain you :
- take a scuba diving bottle, full at 200 bar, at 5°C which is current temperature in my garage, and store it in your garage.
- Come back 1 month later : if temperature is still 5°C, what will be pressure in this bottle ?
If it is less than 200 bar, take your bottle to support…
- And you know what, if spring happens as usual, temperature will be more than 5°C, and you should see that pressure will be over 200 bar.
Not only compressed air storage is lossless, but it can even get you more energy that you have worked to put in…
And you know what ? Just try to put a full battery on your garage, and come back 6 months later to check how much electrical energy you keep inside…
DV82XL said:
Yes in this case you would better use a COP (COeeficient of Performance) as there is heat transfer involved, like for heat pump.
DV82XL said:
Do you mean that power-to-weight ratio is the same concept that energy efficiency ?
DV82XL said:
Do you mean that temperature and pressure of a gaz have no link with energy content of said gaz ?
DV82XL said:
I never thought about applying a heat pump to any argument, but i will try to understand that new field of thermodynamic : you seems very efficient at heating arguments.
DV82XL said:
For me, the 3 stages of :
1- compression ;
2- storage ;
3- decompression.
are quite clear and independant.
I am sure that any decent student in physics can define what inputs and outputs for these stages are, and then will be able to define some meaningful efficiency concept for each of these stages.
DV82XL said:
Do you mean than moving heat has nothing to do with taking energy from one place and storing this energy to another place ?
DV82XL said:
Your teaching is so clear and impressive, thank you so much for this beautiful thermodynamic lesson of your own.
I am sure that your very radical assesment on compressed air car is completely explained by the extraordinary thermodynamic knowledge you show us.
Quote Comment
January 11th, 2010 at 8:09 pm
brnd said:
The bold passage is why you can’t be taught. Nothing, absolutely nothing will give more energy out than goes in. The fact that you insolently assert this demonstrates just how little you understand the subject at hand.
Nor is my assessment compressed air car radical in any sense of the word. The things don’t work as well as their supporters think they will because the laws of physics. The concepts at work here are the Idea Gas Law and the three Laws of Thermodynamics. Please at the very least look them up on Wikipedia before continuing. Then if you want to try and pose some intelligent questions for clarifying some of the ways they apply to air cars, I might answer. At this point the obvious depth of your ignorance makes any further exchange with you a waste of my time.
Unless you demonstrate that you have at least tried to understand these things on your own, I will not answer you again.
Quote Comment
January 11th, 2010 at 9:43 pm
DV82XL said:
Did i say anything against this obvious fact ?
Saying as i did “but it can even get you more energy that you have worked to put in….”
is not at all the same than saying that there will be more energy out than that goes in.
Let me try another way to explain to you :
the natural temperature increase from winter to summer will be enough to heat your scuba diving bottle sleeping in the garage, and heating compressed air inside either.
So in summer, the temperature of your compressed air will be higher than 5°C, and so will be its pressure, exceeding in summer the winter 5°C 200 bars.
You can even take the bottle and, while sleeping and sunbathing, let it laying under direct sun : this is not hard work for you, and i can tell you that compressed air will have more energy to give after a while.
So you may agree :
- that energy in this bottle will by larger in summer than in winter,
- that YOU don’t have to work in order that outer thermal energy come inside the bottle when outer temperature increase,
- and that pressure increase with temperature inside the closed bottle, as described by this famous Ideal Gaz Law you seems to love so much, that you don’t even recognise its application on such a simple situation.
DV82XL said:
Why do you love so much insulting people and give them negative adjectives ?
Did you notice how often such definitive assertion is applying so well to the individual saying it ?
DV82XL said:
It will be a great honour for me to answer any of your questions on my previous posts.
Or do you consider that all other facts i did mention are clear enough and right ?
Quote Comment