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A Question of TemperatureI've been reading more and more about the operations of airships recently and can't decide whether I'm missing something or there is some contradictory information out there.
Some info speaks of the rise in outside (air) temperature and how it degrades the performance of an airship, whilst other reports tell of how sun warming the envelope (and I assume heating the helium inside) provides increased lift. Can anyone clear this up for me? What effect does temperature have on the capability of an airship? the past, present and future of airships : blimpship.com |
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Re: A Question of TemperatureHey there I have created a little blogpost regarding your question.
Hope you enjoy it http://airshipworld.blogspot.com/2008/03/question-of-temperature-warm-air-and.html Regards Andreas On Tue, Mar 25, 2008 at 1:47 PM, blimpship <duncan.rice@...> wrote: > > I've been reading more and more about the operations of airships recently and > can't decide whether I'm missing something or there is some contradictory > information out there. > > Some info speaks of the rise in outside (air) temperature and how it > degrades the performance of an airship, whilst other reports tell of how sun > warming the envelope (and I assume heating the helium inside) provides > increased lift. > > Can anyone clear this up for me? What effect does temperature have on the > capability of an airship? > > ----- > the past, present and future of airships : http://www.blimpship.com > blimpship.com > -- > View this message in context: http://www.nabble.com/A-Question-of-Temperature-tp16274781p16274781.html > Sent from the The Airshipworld Mailinglist mailing list archive at Nabble.com. > > > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > -- Editor of Airshipworld -------------------------------------------------------- Visit the Airshipworld Blog at http://airshipworld.blogspot.com -------------------------------------------------------- _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Heating Helium?Thanks for the blog post in reply to my original question, and yes it was the mention of superheat on the goodyear blimp blog that got me thinking about this.
I have been trawling through my recent internet history to try and find the source of a related question, but can't seem to find it. The question... Why don't we use heated helium to provide increased lift? It would seem that, as helium is an inert gas, there would be no reason why it couldn't be heated within an envelope. Not just in the superheat sense, but in a similar way to hot-air balloons or hot-air airships - why not hot-helium airships? Would it not be possible to increase the temperature of the lift gas in proporsion to the extra lift needed based on the weight of the cargo being carried? It seems so obvious now, there must be a reason that it wouldn't work or surely we would have done it long ago. the past, present and future of airships : blimpship.com |
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Re: Heating Helium?Or maybe I'm going mad and my memory has imploded... Nicholas > Date: Wed, 26 Mar 2008 03:28:03 -0700 > From: duncan.rice@... > To: the-list@... > Subject: [Airshipworld List] Heating Helium? > > > Thanks for the blog post in reply to my original question, and yes it was the > mention of superheat on the goodyear blimp blog that got me thinking about > this. > > I have been trawling through my recent internet history to try and find the > source of a related question, but can't seem to find it. The question... > > Why don't we use heated helium to provide increased lift? > > It would seem that, as helium is an inert gas, there would be no reason why > it couldn't be heated within an envelope. Not just in the superheat sense, > but in a similar way to hot-air balloons or hot-air airships - why not > hot-helium airships? > > Would it not be possible to increase the temperature of the lift gas in > proporsion to the extra lift needed based on the weight of the cargo being > carried? > > It seems so obvious now, there must be a reason that it wouldn't work or > surely we would have done it long ago. > > > > ----- > the past, present and future of airships : http://www.blimpship.com > blimpship.com > -- > View this message in context: http://www.nabble.com/A-Question-of-Temperature-tp16274781p16299635.html > Sent from the The Airshipworld Mailinglist mailing list archive at Nabble.com. > > > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info Get fish-slapping on Messenger Play now! _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Re: Heating Helium?This was used by Picard for the Breitling Orbiter.
The principle is called, Rozière balloon, but I never read about airships that used this. http://en.wikipedia.org/wiki/Breitling_Orbiter_3#The_balloon 2008/3/26, Nicholas J. Rogers <n_j_rogers@...>: > > I'm sure I read about this being done somewhere... Maybe it was in the US > Navy rigids? > > Or maybe I'm going mad and my memory has imploded... > > Nicholas > > > Date: Wed, 26 Mar 2008 03:28:03 -0700 > > From: duncan.rice@... > > To: the-list@... > > Subject: [Airshipworld List] Heating Helium? > > > > > > > Thanks for the blog post in reply to my original question, and yes it was > the > > mention of superheat on the goodyear blimp blog that got me thinking about > > this. > > > > I have been trawling through my recent internet history to try and find > the > > source of a related question, but can't seem to find it. The question... > > > > Why don't we use heated helium to provide increased lift? > > > > It would seem that, as helium is an inert gas, there would be no reason > why > > it couldn't be heated within an envelope. Not just in the superheat sense, > > but in a similar way to hot-air balloons or hot-air airships - why not > > hot-helium airships? > > > > Would it not be possible to increase the temperature of the lift gas in > > proporsion to the extra lift needed based on the weight of the cargo being > > carried? > > > > It seems so obvious now, there must be a reason that it wouldn't work or > > surely we would have done it long ago. > > > > > > > > ----- > > the past, present and future of airships : http://www.blimpship.com > > blimpship.com > > -- > > View this message in context: > http://www.nabble.com/A-Question-of-Temperature-tp16274781p16299635.html > > Sent from the The Airshipworld Mailinglist mailing list archive at > Nabble.com. > > > > > > _______________________________________________ > > The-List mailing list > > The-List@... > > > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > > ________________________________ > Get fish-slapping on Messenger Play now! > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Re: Heating Helium?I'm at work, so I don't have my airship books to hand, but I do recall reading something about experiments with a heating element inside the gas bags. As has been mentioned, it's such a simple idea one would have expected some sort of tests with it. Nicholas > Date: Wed, 26 Mar 2008 11:47:10 +0100 > From: Andreas.Burkart@... > To: the-list@... > Subject: Re: [Airshipworld List] Heating Helium? > > This was used by Picard for the Breitling Orbiter. > The principle is called, Rozière balloon, but I never read about > airships that used this. > > http://en.wikipedia.org/wiki/Breitling_Orbiter_3#The_balloon > > > > > > > 2008/3/26, Nicholas J. Rogers <n_j_rogers@...>: > > > > I'm sure I read about this being done somewhere... Maybe it was in the US > > Navy rigids? > > > > Or maybe I'm going mad and my memory has imploded... > > > > Nicholas > > > > > Date: Wed, 26 Mar 2008 03:28:03 -0700 > > > From: duncan.rice@... > > > To: the-list@... > > > Subject: [Airshipworld List] Heating Helium? > > > > > > > > > > > Thanks for the blog post in reply to my original question, and yes it was > > the > > > mention of superheat on the goodyear blimp blog that got me thinking about > > > this. > > > > > > I have been trawling through my recent internet history to try and find > > the > > > source of a related question, but can't seem to find it. The question... > > > > > > Why don't we use heated helium to provide increased lift? > > > > > > It would seem that, as helium is an inert gas, there would be no reason > > why > > > it couldn't be heated within an envelope. Not just in the superheat sense, > > > but in a similar way to hot-air balloons or hot-air airships - why not > > > hot-helium airships? > > > > > > Would it not be possible to increase the temperature of the lift gas in > > > proporsion to the extra lift needed based on the weight of the cargo being > > > carried? > > > > > > It seems so obvious now, there must be a reason that it wouldn't work or > > > surely we would have done it long ago. > > > > > > > > > > > > ----- > > > the past, present and future of airships : http://www.blimpship.com > > > blimpship.com > > > -- > > > View this message in context: > > http://www.nabble.com/A-Question-of-Temperature-tp16274781p16299635.html > > > Sent from the The Airshipworld Mailinglist mailing list archive at > > Nabble.com. > > > > > > > > > _______________________________________________ > > > The-List mailing list > > > The-List@... > > > > > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > > > > > ________________________________ > > Get fish-slapping on Messenger Play now! > > _______________________________________________ > > The-List mailing list > > The-List@... > > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > > > > > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info Have you played Fishticuffs? Get fish-slapping on Messenger _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Re: Heating Helium?I'm at work, so I don't have my airship books to hand, but I do recall reading something about experiments with a heating element inside the gas bags. As has been mentioned, it's such a simple idea one would have expected some sort of tests with it. Nicholas > Date: Wed, 26 Mar 2008 11:47:10 +0100 > From: Andreas.Burkart@... > To: the-list@... > Subject: Re: [Airshipworld List] Heating Helium? > > This was used by Picard for the Breitling Orbiter. > The principle is called, Rozière balloon, but I never read about > airships that used this. > > http://en.wikipedia.org/wiki/Breitling_Orbiter_3#The_balloon > > > > > > > 2008/3/26, Nicholas J. Rogers <n_j_rogers@...>: > > > > I'm sure I read about this being done somewhere... Maybe it was in the US > > Navy rigids? > > > > Or maybe I'm going mad and my memory has imploded... > > > > Nicholas > > > > > Date: Wed, 26 Mar 2008 03:28:03 -0700 > > > From: duncan.rice@... > > > To: the-list@... > > > Subject: [Airshipworld List] Heating Helium? > > > > > > > > > > > Thanks for the blog post in reply to my original question, and yes it was > > the > > > mention of superheat on the goodyear blimp blog that got me thinking about > > > this. > > > > > > I have been trawling through my recent internet history to try and find > > the > > > source of a related question, but can't seem to find it. The question... > > > > > > Why don't we use heated helium to provide increased lift? > > > > > > It would seem that, as helium is an inert gas, there would be no reason > > why > > > it couldn't be heated within an envelope. Not just in the superheat sense, > > > but in a similar way to hot-air balloons or hot-air airships - why not > > > hot-helium airships? > > > > > > Would it not be possible to increase the temperature of the lift gas in > > > proporsion to the extra lift needed based on the weight of the cargo being > > > carried? > > > > > > It seems so obvious now, there must be a reason that it wouldn't work or > > > surely we would have done it long ago. > > > > > > > > > > > > ----- > > > the past, present and future of airships : http://www.blimpship.com > > > blimpship.com > > > -- > > > View this message in context: > > http://www.nabble.com/A-Question-of-Temperature-tp16274781p16299635.html > > > Sent from the The Airshipworld Mailinglist mailing list archive at > > Nabble.com. > > > > > > > > > _______________________________________________ > > > The-List mailing list > > > The-List@... > > > > > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > > > > > ________________________________ > > Get fish-slapping on Messenger Play now! > > _______________________________________________ > > The-List mailing list > > The-List@... > > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > > > > > > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info News, Sports, Entertainment and Weather on your mobile. Text MSN to 63463 Now. _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Re: Heating Helium?It would seem that the Breitling Orbiter used the natural expansion of the gas at altitiude to provide the extra lift, the wikipedia article stating that the gas bag was filled to only 47% on take off. I have found this short article relating to some Naval School thesis relating to tests on a dual enveloped airship using heating systems inside the internal envelope. "These indicate that the simple use of airship engine exhaust heat will give more than a 30% increase in gross airship lift" I might just have to buy this report and see if we can't get some more info on heating helium in airships. the past, present and future of airships : blimpship.com |
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Re: Heating Helium?The expansion of the gas at a higher altitude does not provide any extra lift.
The higher you fly, the less pressure is around you, so the gas will expand. But as the gas expands, the outside air expands as well. So the weight difference between air and helium that provides the lift, will decrease. That means, the higher you fly, the less lifting capacity the airship will have. This is one of the reason why the big airhships used low altitudes like 300meters. The Breitling Orbiter was using the heating provided by the sun at day. And at night, the temperature of the helium was keeped by burners, to maintain altitude. http://www.breitling.com/orbiter/breit98/eng/projet/techniq/systemes.html I´m sorry for the worse english I´ve to use, while I´m not a native speaker and still training... This heating of Helium is pretty interesting, I´ll do some calculations later on. Greetings, andreas 2008/3/26, blimpship <duncan.rice@...>: > > > Andreas Burkart wrote: > > > > This was used by Picard for the Breitling Orbiter. > > The principle is called, Rozière balloon, but I never read about > > airships that used this. > > > It would seem that the Breitling Orbiter used the natural expansion of the > gas at altitiude to provide the extra lift, the wikipedia article stating > that the gas bag was filled to only 47% on take off. > > I have found > http://www.stormingmedia.co.uk/68/6873/A687381.html?PHPSESSID=610ea123ae919a27de61b87eb7811970 > this short article relating to some Naval School thesis relating to tests > on a dual enveloped airship using heating systems inside the internal > envelope. > > "These indicate that the simple use of airship engine exhaust heat will give > more than a 30% increase in gross airship lift" > > I might just have to buy this report and see if we can't get some more info > on heating helium in airships. > > > ----- > the past, present and future of airships : http://www.blimpship.com > blimpship.com > -- > > View this message in context: http://www.nabble.com/A-Question-of-Temperature-tp16274781p16300790.html > > Sent from the The Airshipworld Mailinglist mailing list archive at Nabble.com. > > > _______________________________________________ > The-List mailing list > The-List@... > http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info > _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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Re: Heating Helium?Hey Everybody,
great to see that my Blogpost started a small discussion. I am missing these discussion ever since the Colorado Airship-List stopped working. I wish there were more people on this list. It would be great to see this list flourish and to become something like the Airship-List, so if you know people who would be interested invite them to join the List, it's a Forum just as much as it is a Mailinglist. I don't know if the Airship-list exists anymore or if it is gone for good. But in the meanwhile I think we are able to fill this void with our cozy small list. Thanks everyone who has already subscribed. Regards Andreas |
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What about colour?In reply to the comment from Andreas...
...it certainly did. Now I've got a related question - I remember from learning about aircraft years ago that the reason most aeroplanes are white is because it reflects the suns heat and prevents the aircraft overheating. There was a story about Pepsi sponsoring a Concorde and having it painted blue, but the new livery meant that the plane built up so much heat that it was unable to fly! For the same reason Stealth Aircraft are black, as the plane does not emit so much heat and thus avoids detection. So the question is... ...would a black envelope store heat better and increase lift? By this I mean, if we assume that heated helium would increase lift (superheat) could having a black envelope help maintain this higher temperature? The suns heat would still warm the envelope, the black colouring would prevent the heat dispersing too quickly and an internal lift gas heating system could all combine to give a lifting capability which exceeds the size of the envelope. If I'm wrong - tell me why If I'm right - you can name the first black blimp after me! the past, present and future of airships : blimpship.com |
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Re: What about colour?Hi all,
blimpship asked: > ...would a black envelope store heat better and increase lift? To my knowledge, regarding heat, the black envelope would do 2 things simultaneously: 1. catch solar radiation and heat up. When the the gas inside is cooler, some of the surface heat gets transfered to the inside. 2. radiate. Deep black is a very good heat radiator. So, a black surface warms and cools at the same time. Additionally, 'Fly wind' wil cool the warm surface, starting heat transfer form inside to outside. Where the equilibrium in this story lies, I have no idea. My hunch is that it will work, because it works too for those small cigar-like toy blimps. Additional internal heating, that's another questionmark: how, where and with what extra gear, weight? Is the lift from this all just enough to compensate itself? Mart | Rotterdam > By this I mean, if we assume that heated helium would increase lift > (superheat) could having a black envelope help maintain this higher > temperature? The suns heat would still warm the envelope, the black > colouring would prevent the heat dispersing too quickly and an > internal lift gas heating system could all combine to give a lifting capability which > exceeds the size of the envelope. > > If I'm wrong - tell me why > If I'm right - you can name the first black blimp after me! _______________________________________________ The-List mailing list The-List@... http://airshipworld.info/mailman/listinfo/the-list_airshipworld.info |
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