Camper Thermal Engineering for Extreme Cold & High-Altitude: Arctic Antarctica Tibet

campo

Adventurer
Hello Biotect

Of course I will try to make some thermal calculatons on Terraliner
It is good that you gave some extra imput with the dimmensions.

I have the k-values for the KCT windows and glass as the ones from Seitz and for a simple Fiat ducato Windshield glass.
This is my source that I used also for the information about k value with rollers shades closed.
Sorry but it is in German (no problem for EGN and Thajiks) but have a look at the pics, certainly the ones made with the FLIR camera.

http://www.building-physics.net/webfm_send/603


It will take some time but the calculation results follow

Best Campo
 

cwsqbm

Explorer
If it's a choice between a thicker floor or a thicker ceiling, which would you choose? In the DoLeoni MAN KAT posted earlier in the thread, the floor is 14 cm thick, and the ceiling 10 cm thick -- see http://www.doleoni.com/wp/en/man-kat-1-a1/ . Any idea why the floor of the DoLeoni MAN-KAT would be more heavily insulated than the ceiling?
For insulation purposes, a thicker ceiling is better. The floor won't get solar exposure for heat, and is slightly protected by the truck chassis and storage boxes for cold. The reason a particular box may have a thicker floor is that the floor is also has to be a minimum strength to support loads such as people. Given that the side walls are limited in thickness (because of vehicle width restrictions and a desire for a roomy interior), there's a practical limit to ceiling and floor thickness anyways.
 

campo

Adventurer
Yes I do agree with cwsqbm the sun o, the roof is the biggest problem.
Cooling down in Summer is more problematic than heating up in winter.
Also consider that you have a second insulation layer inside: The furniture.
That covers for a big part the walls and the floor but not the ceiling.
Wall thicknesses of more than 60mm makes it difficult for doors and windows to open.
Thick walls reduce the space inside and bring no extra strength.
The need for extra thermal power to heat or cool down the habitat is regarding the relatively small size not that important.
For the roof and floor I would use 60mm, For the walls 50mm and even 40mm is possible.
Do not look to much at what some strange people are doiing. First open some RV doors of 100mm and you'll agree that that is not a good idea.

Regards Campo
 
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biotect

Designer
Hi Campo,

Many thanks for responding!

I have to confess that I don't really understand your "door argument". Couldn't the doors just be made thinner? Why do the doors have to be 6 cm thick, because the walls are 6 cm thick? Couldn't the doors be just 4 cm thick, and so light enough for elderly couples to use? After all, the windows are not the same thickness as the walls, either. So couldn't the doors be thinner than the walls, too?

When you did calculations for 6 cm wall-thicknesses instead of 4 cm earlier in the thread, thermal efficiency did improve significantly, didn't it? Yeah, I know that one can always add another heater. But more heaters will use more diesel fuel and/or electricity, and one objective with a vehicle like this is having the ability to "boondock" for at least 3 weeks, and ideally a month, or even longer. "Boondocking" means living in the middle of nowhere, with no contact with the outside world, living completely independent, just using the fuel, food, and systems available in the camper. So if the walls were slightly thicker (6 cm instead of 4 cm), and this could cut down on fuel consumption, that would make boondocking for lengthy periods easier, even in the middle of a Siberian winter. Or boondocking in the middle of the Sahara, with less drain on the A/C system.

Remember, I have never proposed thicker than 6 cm for the walls, and I realize that a wall thickness of 7 or 8 cm is totally unrealistic and undesirable. But I am really curious to know how the numbers would work out for one set of "minimal" calculations, with a wall thickness of 4 cm, and ceiling/floor just 6 cm; versus another set of "maximal" calculations, with a wall thickness of 6 cm, and ceiling/floor 8 cm; or the floor 8 cm, and the ceiling 10 cm thick.

In any case, I have posted lots of new material in the "TerraLiner" thread ("Man or Tatra....."), which you might find interesting. Many of the posts there were addressed to you, in response to some of your thoughts in that thread. It would be great if you could add to the discussion about IS (independent suspension), and also repost your material about the Volvo independent suspension system for trucks (your previous attachments did not work). You might also enjoy my most recent post, about a MAN-KAT conversion that crossed Siberia in the winter.

Campo, you are a mensch, and I am really glad that you are now a regular contributor to ExPo!!

All best wishes,



Biotect
 

campo

Adventurer
Hello Biotect

About the door thickness: You can make the plate in the middle of the door as thick as you want but the surrounding will always be the problematic insulation point. The rubber joints there are important and have to be without thermal leaks, like you find them on deep freeze transport vehicles. Only these rubbers get cold and you have to pull with two hands to be able to open such a door. So from the insulation point of view there is no objection but these thick doors become realy unpleasant to open. Consider that you have to open the doors the whole year long and not only these few cold periods.
Its common to use the same panel thickness for the doors as for the walls.
.
Of course the thermal efficiency improves with better insulation. Althoug 17% improvement seems a lot (from 40mm to 60mm) it is on such a small habitat volume realisable with the same diesel heater. So you will not have to buy or install a bigger heater. You have to consider that the bigger problem is to build a heater system that can do both. Run for very long periods on idle ( between outside +15°C to 0°C) and somethimes for relatively short periods on maximum power (at -40°C). The major reason for not building an oversised sytem (and insulation) is that it can destroy the good combustion as the system will probably have to work on idling for >80% of the time. (you get sooth in the burner as it runs to cold on idle for long periods. Oversized. This is also why I do prefer to use 2 small heaters in stead of 1 big. The normaly used water heaters are 5kW or 10 to 12kW for this application. For your +10m vehicle I will propose the 12kW water heater + as backup an air heater of 4kW or 2 air units of 2kW. I know that already before making the calculation.
.
With the maximum of 16kW you will never have problems at the few very extreme cold situations. (even at 40mm or 60mm)
More problematic is that you will need between 1 and 4 kW heat during 90% of your travelling...with the same heater(s)
.
As the diesel combustion efficiency is 85% the fuel consumption for the heater is not that important.
In my estimation you'll need about 10 litres/day gasoil/diesel at the extreme -40°C for your vehicle. Yes 17% is 1,7 liters.
.
I have to look at the IS Volvo pics that i thought I already placed again.

All the best from Campo
 

biotect

Designer
Hi Campo,

Many, many thanks. OK, now I get it. Your main point seems to be that there's a real problem of "over-insulating" the vehicle; very interesting, as always. Looking forward to your calculations for the TerraLiner in this thread, as well as the Volvo IS info in the other thread. Only problem now seems to be that the two participants who have defended the traditional straight-axle approach -- egn and thjakits -- have not been commenting in the other thread...... Perhaps because they realize they are outnumbered? Everyone else seems to agree with you, campo, that Independent Suspension is the way to go. So your Volvo IS information would be interesting, because it's another example of IS in a heavy truck application. So far we only have info in the thread about Oshkosh TAK-4.

All best wishes,



Biotect
 
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adam88

Explorer
I don't know what to make of this thread. It seems like the most intense thing I've ever seen. It crashed my computer twice just trying to load it. My head hurts...
 

biotect

Designer
Hi adam88,

If you think this thread is intense, check out http://www.expeditionportal.com/forum/threads/124789-Fully-Integrated-MAN-or-TATRA-6x6-or-8x8-Expedition-RV-w-Rigid-Torsion-Free-Frame .

Yeah, both threads should probably come with some kind of computer-capability warning:

WARNING

Minimum Computer Requirement:

-- Broadband Internet
-- 2.8 GHz Intel Quad-Core i7 Processor
-- 1 TB Flash Storage, 16 GB memory
-- Intel Iris Pro Graphics +
AMD Radeon R9 M370X with 2GB GDDR5 memory

That's the configuration of the MacBook Pro that I am now using to create these posts. If you have an older computer (say a 5-year old MS-DOS based machine), you probably won't be able to download the image galleries quickly and easily. And your graphics card is probably way out of date.

I figure that as the general stock of computers becomes faster and more capable, and as people gradually dump their old machines, eventually the capability of the average machine will far outstrip the computational complexity of these threads. So 5 years from now, these threads should be easily readable by just about any machine on the market, even the low-end, low-cost ones.

All best wishes,



Biotect
 

Recommended books for Overlanding

biotect

Designer
..
Fantastic work and consolidation of documentation and imagery/video.

I am not a fan of the cold, but somehow always end up in it ;)

Dear Scott,

You understandably cannot accept private messages, but I seem to be having a problem making contact with the forum administrators. I've now written to them twice about wanting to change the title of another thread, a thread that I also began. I wrote them the following two messages:


Dear Forum Administrators,

If possible, I would like to change the title of a thread that I began, but have forgotten how to do so. The current title of the thread is "Fully Integrated MAN or TATRA 6x6 or 8x8 Expedition RV, w Rigid, Torsion-Free Frame", and I would like to change the title to:


TerraLiner: 12 m Globally Mobile Beach House/Class-A Crossover w 6x6 Hybrid Drivetrain


A change of thread title has been long overdue.

Any suggestions?

All best wishes,


Biotect


PS -- this message was not sent to "mountainpete" only because it seems that he has exceeded his quote of stored private messages..... So I had to remove his username from the list of recipients.
Dear Forum Administrators,

I did a "Test" on the forum, by creating a new thread, naming it, posting it, and then going back into the thread to rename it. It is just as I had thought: if one creates a new thread, and then if one goes back and edits the "title", not only the title of the post changes, but so too, the title of the thread automatically changes as well. So in principle there should be no problem changing thread titles. Change the title of the first post, and one changes the title of the whole thread. At least when it comes to relatively new threads.

Now I did exactly the same for "Fully Integrated MAN or Tatra....", but only the title of the first post in the thread changed. The title of the thread as a whole remained fixed and unchanged. So in the case of the "Fully Integrated MAN or Tatra...." thread, somehow the system no longer works on the automatic default that if one changes the title of the first post in a thread, then the title of the whole thread changes as well.

I really would like to change the title of the whole thread. So if possible, please reply as soon as you can. Changing the thread's title is important from a user point of view, because the new title much more clearly signals what the thread is now about, and where it is going. Some thread participants have recently expressed a certain degree of confusion regarding the thread's "theme" or "direction", and the thread certainly has evolved since it was first started. So it seems important to change the title, to dispel confusion.

All best wishes,



Biotect

Sorry for writing to you about an administrative matter pertaining to another thread, in this thread. But I was not sure how else to get some kind of response to my query.

All best wishes,



Biotect
 

sargeek

Adventurer
Interesting thread- but you are way overthinking what the United States Antarctic Program does on the ice. I was involved in the 95/95 season at the old dome station.
All programs being run are siege style expeditions - lots of people, money, equipment at minimal risk to personnel. This is way different to expo-style expeditions. Expo style expeditions are more alpine style: fast and light, self contained. However, the US has been operating on the ice for a long time and has an impressive insutional knowledge of what works and what fails.

For example I will pick on a van they delivered to the pole to transport scientists to the telescopes on the other side of the station. It was a Ford E-350. The van went to an up fitter who installed four wheel drive; lifted it for the 44" tires. Addional modification so were minimal. Then interior body panels we removed and an additional layer added. They neglected to install a lever for the transfer case - because someone thought it would be in 4-low all the time (fail); so we had to crawl under the rig to shift it. Other modifications were limited to a second battery in parallel. They installed battery blankets, left and right freeze plug heaters ; and Emersion heaters in the atf pan and the oil pan. These would be off the shelf items from a supplier like KATS. Everything else on the vehicle needed to meet US laws. Mechanics were unable to remove items such as catalytic converters or other emissions equipment.
The radiators ran 100% glycol,'and the fluids were suitable for the cold.

It was interesting at McMurdo the US vehicle ran 44" tires while all the vehicles used in the New Zealand program had stock tires. In the summer months I was their never saw the advantage of them super sized tires.
 

diegop

New member
Practical glass and hatches insulation values:
.
The nice KCT solution has a very good reputation. Main reason is that it is one of the only ones offering such a product.
As you can already imagine I am not so impressed by the KCT window’s:
- Very pore glass insulation value (KCT announces Ug 1,3 W/m²K but we found out that the KCT double glass is probably more something like 3,0 W/m²K.
The window frame value Uf is not announced)
- Huege framework, almost 1/3 of the window surface
- High price
- Weight is high
- Integration of the rollo could be better
- High altitude solution is debatable
.
Competitor for KCT today is Outbound in the Netherlands who offers better prices for similar products.
.
Fiat OEM Ducato wind screen
Front wind screen Fiat Ducato (camping van RV):
isolation 5,71 W/m²K
lucent transmission 78,0 %
energy transmission 52,1 %
.
Side screens OEM Fiat Ducato:
insulation 5,71 W/m²K
lucent transmission 83,8 %
energy transmission 86,2 %
.
RV plexiglass Windows Seitz S4 and hatches Seitz (Acryl) double
insulation 2,4 W/m²K and 1,65 W/m²K with closed curtains
(so it is important to close them when cold or warm environment as by night)
lucent transmission 73,5 %
energy transmission 60,0 %
(laboratory values given by the producer and maybe a little optimistic ?)
.
Double glazed windows GEBO Thermic Line :
(values from glass calculation program www.yourglass.com/configurator)
introduced values :
Exterior glass 6mm Planibel Dark grey
air gap 9 mm 100%
Interior glass 5 mm Planibel Clear
(you can introduce argon as gas for better results but double price)
.
Results of the simulation Gebo double thermic glass:
Ug value : 3,0 W/m2°K according to EN 673
With mentioning the possibility for important improvement by closing the curtains.
Light transmission (Tv) 7 ... I do not know what that means
Total energy ABSORBTION 89% … strange absortion is not transmission
.
Gebo low profile hatches 24mm (Flushline) similar to Lewmar used on boats.
I think you can use values for the GEBO hatches from acrylic simple glass 8mm Acryliques Gebo
with a coefficient of +/- 5,0 W/m²K. When you close the curtains it will be a lot better like 2,0 W/m²K
Do you know if the Gebo configuration you suggest will support 5000m above sea level?.. I´m tryng to spec a glass that will do..

Many thks.
 

thjakits

Adventurer
Hi all!
I am not sure (anymore..) which other threads biotect refers to further up (except his own..), so I put my opinion here:
- Yes, the trend unmistakable goes towards Independent suspension! As it did for a long time in FAST offroad sports. In the end, it doesn't really matter: At the proposed vehicle size (full size non-articulated truck) and sensible max speed on and offroad you can make any system "feel nice".
For the proposed purpose of Biotects ride it will probably by IS - you are NOT going to take your rolling home rockcrawling, are you?
Personally I still might go for straight axels, for less complexity - if you don't plan to work on your machine, this point is moot.
- Another point Biotect posted on his approach in the past was - it must be hybrid! WELL, that was a few years ago (....must be one of the longest ever threads on here!) - it seems TODAY and technology progress seen today will definitely go towards FULL ELECTRIC period.
The one thing to still be solved is charging in the boonies - what to do if you don't have charging dock? ...then you could argue, well what to do if you don't have a gas station?? Bring enough charge! ...additionally - solar is still getting better bby the day. Batteries are on the way out shortly (...still curious about Teslas latest batter-tech patent and change), my bet is on Hybrid-Hyper-Capacitors, as in https://newatlas.com/energy/toomen-powercapacitors-kurt-energy-high-density-supercapacitors/ - for now take a mix of the 2 discussed ones...
Charging rate limitations are only on the Charger capacity, not on the Capacitor - if you can provide Mega-Ampere facilities, charge in seconds!

The REAL problem for the Terra-Cruiser is not really anymore what you want to do - but how fast technology changes today - by the time you put your latest "breakthrough"idea into CAD - it's already obsolete again!

Cheers all,

thjakits
 
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