Superpiper, the CAESAR II file you talked of, in no way corresponds to my final model now. However my reply to your comments follow:
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*has no pressure????................ i set +ve, zero and negative pressures to see the difference CAESAR II behaves, nothing more in it!
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*is filled with gas at 7833kg/m3???........... What is wrong in Pipe density picked from Ceasor database?
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whats wrong with fixing it in the middle and using a simple COMPENSATOR at both connections?..............This is the simplest approach that comes to mind first; and this is exactly how i designed it in the shared CAESAR II file. It resulted in a simple COMPENSATOR on one side of anchor that required 36 convolutions which Pathway professionals say "No one shall manufacture it". In place of 36 convolutions simple EJ, i have used 3 hinged EJs on a changed but more simple route.
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why are you using 1/2" thick pipe?........... This much wall thickness donot require pipe stiffeners. Thicknesses more than 11 mm would be addition of huge costs for such large dia long pipes.
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why support every 6m??????..............Yes, this is something i had to see a lot many times while deciding about it. Since it was thin pipe (high d/t ratio), so very suspectable to buckling! A well restrained system having guides at appropriate spans should never buckle down. Moreover, the line needed to be stiffened laterally so as to face huge wind loads. I curtailed support span equal to span for guides.
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should Ceasar be used for this???? (Bends???)...........Why not? piping flexibility and buckling are different issues to be handeled. For d/t>100, the issue of piping flexibility can be handeled through usage of correct SIF values.Our understanding is that for flexibility analysis, the problem lies with SIF values and not with Ceasor II. FEA calculated SIFs will cater the problem. However the issue of buckling should be investigated independently and shall however remain to be analyzed. Ceasor II has never been a tool for analyzing buckling issue, not even for d/t<100. Please correct me if wrong.
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Can those mitre bends take large deflections?........ I have used hinged EJs in my final solution, the deflection shall get compensated else where with minimal impact on miter bends. Application of correct SIFs is however needed.
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is the earth flat????......... Depends where you are seeing it from.
Valid points SOS,
I have actually done this, and i couldnt get it out of my head that a speciallist flue duct firm would have done it twice as good for half the cost using duct.!!!! (my client wanted c22-nuts)
When i say no pressure, 1.5 psi is almost negligable (and to be expected)
When i questioned density of GAS! i made a mistake and read your gas to be
7833kg/m3 - oops !
When i questioned using compensators at the ends, i meant fabric expansion joints, not convoluted ones, fabric ones are comenly used in flues due to the very large deflection they can handle, and the relatively low pressures required (see point 1) if you tried that, fair enough, but Convoluted EJs would be somewhat expensive.
When i questioned 1/2" pipe, yes it may eliminate stifferners, but the cost of supporting and purchasing such huge pipe may well exceed that of simple duct with stifferners.
Its normal practice to use sheet ducting, with plate flange sections every 6m or so that the pipework is naturally stiffened, also the sections are easily replace in the event of high corrosion (very likely)
Pipe supports require money and a structure to sit on, plus with the weight of your pipe, the sliding forces are quite high. Head transfer to the shoes could be over the normal PTFE limit of 225c (ish)???
At those temps, the PTFE pads are going to squash, Possibly creating a "sink" for the shoe to sit in.
Should Caesar be used? i don't honestly know. It will give a good indication of the global effects, but i would wonder about the accuracy of the local effect. Beam theory does not translate well here i believe.
WRT the earth,
A bit o light humour.
To close.
The amount of money and time required to have this line installed, supported and stressed may well exceed that used by proffesion flue duct companies. My first port of call would be with the "incinerator?" manufacturer to see if they have a natural way of ducting the flue gasses to the stack.
Just because your 1/2" thick pipe works, doesnt make it the correct option.
But, i am only suggesting!!! you are there, and are best to make that call.
The final layout you posted looks overengineerd and excessively expensive, although it might be correct.
Good Luck
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