Ok, point taken, you want hard numbers, I don't have them.
I doubt if you will find them but if you do then please post. If the hard scientific answer is what I think it is then there will be a lot of very unhappy CO2 bashers and research budgets may be slashed. In the interim I resort to...
In recorded human history there have been periods of extreme cold at times well before industrialisation and when the human population was low. This is backed up with Ice core data and some tentative links have been made with strong volcanic activity.
Given that the extremes of climate were...
I think that volcanoes have an enormous impact on global climate. The "Dark Ages" period of ancient Britain has been postulated as a time of very poor harvests and general cold. This has has been linked (perhaps debatably) with an enormous volcanic eruption in the mediteranean at that time.
I...
...the world has 66 years of gas, 40 years of oil, and 164 years of coal. Source is BP annual survey which matches US DOE EIA fairly well.
Then we had better start changing ****ing quickly because those time scales are a blink of an eye in human civilization terms, non-existent in geological terms.
I found some more recent numbers for wind turbines and PV cells. For modern PV cells, the energy payback time is "a few years" and the cell life up to 30 years. For wind the payback is an astonishing 3-5 months and machine life - well as good as you can make it, say 25 years?
I still reckon...
Aaaaaaaaaaaallllrightey, thanks Wally.
> If you are not a liberal when you are young, you have no heart. If you are not a conservative when you are old, you have no brain.........Winston Churchill.
One of my favourite quotes [2thumbsup]
I suggest you raid the Hexcel web-site for methods data sheets, the data sheets are quite good but I'm not sure if they have put them on the web-site yet.
OK. Well I model sandwich panels using shells for the carbon plies and bricks for the honeycomb/foam. I do this because sanwiches are usually so thick that you end up violating the shell thickness to element edge length limits (you may have a shell which is 5xthicker than the shell edge length...
Seems like you'r asking how to analyse a sandwich panel rather than what allowables to use. By manufacturers data I mean the manufacturers of of the Rohacell and carbon.
In terms of what you do with the numbers. How have you modelled it? This will influence how you treat the allowables.
In the UK at the moment there are strong mutterings about building more nuclear power stations. I feel this may be intrinsically sensible given that we already have about a dozen very radioactive sites anyway, some with active plants, some not.
However, someone told me that if you evaluate all...
Well, I claim a foot-fault on the Goodwin caller Rhodie because the Hitler comment was an aside to an individual and not used as a basis for argument.
((:-)))
Hmmmmm.
Wally, apology accepted. The cute and humourous emoticons helped. By the way, how do you incorporate these things into posts, is it part of the :-) set? I suppose I'll see when I hit submit.
sms, "we just buy oil and happily" - are you serious?
rhodie, This thread has been "Godwin'd"...
Engforum78,
It is just a coincidence and there is no linear relationship. For a lot of metals, the stronger they are, the stiffer they are.
A simple exception is Titanium which is not very stiff compared to steel but is stronger than many steels. Titanium is not, however stronger than the...
BigWallyB,
I take all of your points graciously, but I resent insults like "Come on. Talk about politically biased thinking".
My points about resource depletion, over-population, and the USA only seriously comitting when oil is involved are fair and true. Don't drag Korea and Vietnam into...
