Aqu 08, 01 / Jan 8, 17 08:20 UTC

Re: Heat transfer and dissipation in space: let us build a team with interested volunteers  

Still a problem of increased number of moving parts, and only considerable as a contributary effort.

The "improvements" in efficiencies cited there are concerning it's ability to convert heat into electricity, more than it's ability to dissipate heat. That design specifically intended for RTG's, which operate at a much lower thermal output than a coolant system - watts as opposed to the kilowatts currently dissipated by ISS, or the gigawatts possibly even terrawatts we'd need to consider - and is using exposure to vacuum to provide for the cooling part of the cycle. This sort of thing placed into the primary heat exchange system will require to vent that temp into the environment, ending back up in the system again. Placed on the secondary heat exchange that takes to the radiators or on the radiators themselves could afford it direct external coolant - but this is likely to be effected by the same heat dissipation issues, and likely pick up a lot of external temperature radiated from nearby stirlings(it would require some density to provide for even a minor impact) or from the system itself.

As we are unlikley to require the electricity this is intended to generate, the less efficient the carnot cycle, the more energy it should be able to dissipate out of the system as much can be intentionally wasted.

  Updated  on Aqu 08, 01 / Jan 8, 17 08:27 UTC, Total number of edits: 1 time
Reason: typo

Aqu 08, 01 / Jan 8, 17 18:13 UTC

Hi WoefulZeus. I have looked video about linear Stirling engine and I steal have few questions.

First, why Stirling engine? If you imagine space station like ISS, try to calculate how many Stirling engines you will need for the dissipation of small amount of heat to maintain constant temperature. Using this technology you can't build giant engine that will solve the problem, so, you will need dozens of smaller ones. And where you find free space for all that machinery? As I know, there are not much available space on ISS.

Second, any mechanical mechanism will generate vibration with certain frequency. As known, in some cases this may lead to resonance with parts of the space station or with astronauts (this may cause problems with health). And, as EyeR noticed, such engine needs medium, so it will transfer heat from one medium into another and only after will be possible some dissipation through radiation or etc.

Aqu 08, 01 / Jan 8, 17 21:54 UTC

Hi everyone, Marjan is here. I have communicated with the admins and they asked me to be patient since a place with limited access that we can put our proposal is coming :)! They just did not mention how long we should be patient. But still fine.

I cannot share the design of my chamber since we have decided maybe to patent the device. As soon as I know what I am supposed to do with it, I will share it with our team.

As IT team has suggested, I continue polishing the so-called first draft of proposal.

Thanks everyone one for all your comments.

  Last edited by:  Marjan Zakerin (Translator, Asgardian, Candidate)  on Aqu 09, 01 / Jan 9, 17 09:20 UTC, Total number of edits: 1 time

Aqu 13, 01 / Jan 13, 17 14:35 UTC

Dear Heat dissipation Team, i had an interesting experience. Yesterday I heard a talk from Sir Friend "http://www.phy.cam.ac.uk/directory/friendr". As far as I was told he has 5 companies. I had a short conversation with him. They have discovered that a triplet state in organic electronics is very useful. As far as I understood it is very much useful for us too.

Sth that suprised me a lot was that we discussed together almost all the conversations we have had here. I asked him what he thinks about change of heat to light based on what he has discovered. You might think I am crazy but it seemed to me as if he either was in the team or was reading our discussions. I personally suggest that we also take a look at organic electronics. There are many things to be learned from them too.

  Last edited by:  Marjan Zakerin (Translator, Asgardian, Candidate)  on Aqu 13, 01 / Jan 13, 17 14:52 UTC, Total number of edits: 2 times

Aqu 14, 01 / Jan 14, 17 00:54 UTC

Heat » light is a way of dissipating some energy - but it's still not going to make a dent in the overall system... It's a complimentery technology more than a primary dissipation method. Mechanical means like stirling would eat more actual energy out of the system. But leveraging such metamaterial effects and other "interesting" things it should reduce the requirement to use electricity for lighting - which I feel would impact on thermal load more than the conversion to light.

Aqu 14, 01 / Jan 14, 17 11:49 UTC

EyeR@ thank you so much for your comment. I am very happy to have the chance to get comments from experts like you, Artem and the other team members.

Aqu 14, 01 / Jan 14, 17 14:09 UTC

I'd in no way describe myself as an "expert" - just "interested". However my interests are varied, and this results in understanding of a wide range of principles.

As I mentioned with regards to carnot cycle in stirling engines, a less efficient conversion process utilised in extracting energy from the excess thermal energy could result in significantly higher energies being removed, increasing the effectiveness of the complimentary technology, in terms of removing heat energy. But the primary system - for anything "significant" is going to be ... intense. I'm currently unable to envision viable solutions beyond "increase surface area". This is naturally problematic in as much as it increases vulnerable surface area, and gives more places for problems to actually happen - to assume it pumps liquid in a grid array, then each intersection on that needs a valve to prevent it bleeding coolant into space if it's breeched... increasing size increases mechanical complexity, and gives rise to more things that can go wrong.... Simple systems tend to be the most effective, the simpler the better... A system isn't perfect when you run out of things to add, it's perfect when you run out of things to remove. Preferably that simple it operates on the laws of physics itself - like the metamaterial lighting - and thusly failure quite simply isn't an option. Ofc, not everywhere needs lights - especially constantly. Although some sort of iris or shutter could serve to solve that. But even using the entire exterior hull it's unlikley to remove significant quantities.

As well as the biological thermal output with mass habitation, I predict various industrial mining processes to generate vast amounts of heat. It might be possible to render asteroids to smaller, processable chunks with resonance, these chunks should easily powder by mechanical means - various techniques can sort all at relatively low temperature - but things like smelting iron are really going to require some serious dissipation. And we really need to be doing things like that up there, or we've got no chance of getting the bits together to build places for us to be. There's too much required to lift form the surface - it's too heavy, would take too many trips. By the time the mulitple trips are complete, our grandchildren would be dead. And it would of raped the Earth bare in the attempt. Taking it from up there can happen a lot faster if you do it right, impacts the Earth minimally, and the process of which will open up the abundant resources of the universe for harvest. Almost everthing is ready for that to happen - some things just need a little tweak... Thermal dissipation is definitely one of these things. In the case of mining, it should be possible to use a modular design where a heated crucible is then removed, and it can be disconnected from the facility to prevent it bleeding it's heat. The setting of that into a usable material is likely to require a slower gradient than space would naturally provide so some of that thermal energy can be recycled there... That and a few other industrial processes I predict to be problematic in this regard.

Aqu 16, 01 / Jan 16, 17 13:58 UTC

Hi everyone, today I listened to a talk called ""The Alchemy of Vacuum - Hybridizing Light and Matter”. It was very relevant for us and the heat dissipation in space. I was super excited. Prof. Thomas W. Ebbesen, ISIS & USIAS, University of Strasbourg/France was the lecturer. Dear Artem, It must be very interesting for you as a biologist too.

Basically I am in wrong group. I must talk to the molecular electronic head.

  Last edited by:  Marjan Zakerin (Translator, Asgardian, Candidate)  on Aqu 16, 01 / Jan 16, 17 14:38 UTC, Total number of edits: 1 time

Aqu 17, 01 / Jan 17, 17 17:31 UTC

Hi Marjan.

I guess that talk was really exciting and very interesting (I have found in internet abstract of that speech and it was very promising).

Aqu 18, 01 / Jan 18, 17 13:01 UTC

No one has ever measured or calculated heat conductivity in this confined area. He told me if you are interested, do it.

Leo 04, 01 / Jun 21, 17 14:47 UTC

Absolutely vital research! I planned a cubesat experiment in my first year of grad school that never got funding on superconductivity in vacuum. Simple and important. If putting a HTC in the shade can drop the temp down low enough for phase transition .... then we are golden with power transmission and many other inevitable uses for superconductivity. The hardest part of the design was packing a deployable shade and a long radiator antennae into the tiny cubesat and separating this from the electronics of the experiment. I am so ready to get to work on this stuff again!

Cap 11, 01 / Dec 13, 17 12:18 UTC

На орбите земли проблема России тепла дополняется необходимостью сидел от Санчо излучения.Самое простое решение-НД огромный черный шар покрытый с единственной стороны отражающим слоем с пренатальной конвекции теплопроводящего газа(дерева или гель).Причем если сделать Sole полусферу porch а в нем прошлое притчи зеркало то сливы решение по выработки энергии на порядок дешевле кремниевых элементов.Проблема с устойчивостью La plano к ultraviolet и Сонни vet-должно быть что-то похожее на стеклоткань в STL другого состава но с тем же коэффициент как попало или надо какую то педусматривать регенерации путем нанесения покрытия изнутри либо снаружи-например вакуум Пленума того же стекла.

In earth orbit, the problem of heat dissipation is complemented by the need for protection from solar radiation.The simple solution-a huge inflatable black ball is covered with a Sunny side reflective layer with a forced convection heat-conducting gas(hydrogen or helium).And if you make a transparent solar hemisphere and in the middle put a parabolic mirror then will get the solution to generate energy cheaper than silicon cells.The problem with the stability prozrachnyh films to ultraviolet solar and wind-should be something similar to fiberglass in glass of a different composition but with the same refractive index or the need to predusmatrivaet what that regeneration by coating the inside or outside-for example by vacuum deposition of the same glass.

Cap 11, 01 / Dec 13, 17 12:19 UTC

На орбите земли проблема рассеивания тепла дополняется необходимостью зашиты от солнечного излучения.Самое простое решение-огромный надувной черный шар покрытый с солнечной стороны отражающим слоем с принудительной конвекцией теплопроводящего газа(водород или гелий).Причем если сделать солнечную полусферу прозрачной а в середину поместить параболическое зеркало то получим решение по генерации энергии на порядок дешевле кремниевых элементов.Проблема с устойчивостью прозрачных пленок к ультрафиолету и солнечному ветру-должно быть что-то похожее на стеклоткань в стекле другого состава но с тем же коэффициентом преломления или надо предусматривать какую то регенерацию путем нанесения покрытия изнутри либо снаружи-например вакуумным напылением того же стекла.

In earth orbit, the problem of heat dissipation is complemented by the need for protection from solar radiation.The simple solution-a huge inflatable black ball is covered with a Sunny side reflective layer with a forced convection heat-conducting gas(hydrogen or helium).And if you make a transparent solar hemisphere and in the middle put a parabolic mirror then will get the solution to generate energy cheaper than silicon cells.The problem with the stability of the transparencies to UV light solar and wind-should be something similar to fiberglass in glass of a different composition but with the same refractive index, or it is necessary to provide some regeneration by coating the inside or outside-for example by vacuum deposition of the same glass.

  Last edited by:  Rem Krivonos (Asgardian)  on Cap 11, 01 / Dec 13, 17 18:35 UTC, Total number of edits: 1 time