ExpatOilWorker

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About ExpatOilWorker

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  1. If the plan stop mid air, I don't think a seat-belt would make much difference to the outcome.
  2. The title should read: Thailand invites the world to enjoy the glorious (fake) tulips of Chaiyaphum They are not actually tulips, but some kind of weed.
  3. 3 years ago the sock was on the other foot. http://time.com/2825037/thai-thailand-coup-junta-pr-girls
  4. Bit late for that, they just wasted billions of pounds having their little war on Iraq and Afghanistan, all in the name of protecting country and flag.
  5. You mean up to European standards. Looks like the UK had a lot to learn before they left the EU. http://metro.co.uk/2017/06/16/why-is-cladding-banned-in-the-us-and-germany-used-on-buildings-in-the-uk-6712578
  6. Build it next to a LNG re-gassification plant. Thailand plan to import 10 million tons of LNG per year. That should keep your servers crisp and cool.
  7. My dear mother in-law, what are you doing standing alone in the doorway in the rain - just go home! NB: Actually I have the worlds greatest mother in-law.
  8. It did get refurbished with new cladding in 2016.
  9. Well played. Since I mostly do city driving I only get 5 km/l, so 12 baht might get me 2 km on a good day.
  10. You could have saved a whopping 12 baht when topping up the mighty Vios.
  11. Ask yourself who make the bulk on money of oil and gas and your dream is suddenly moving a bit further away? The answer is states and governments, through tax, royalties and national oil companies. Poor little ExxonMobil and the other International Operators are just getting a few breadcrumbs left on the floor.
  12. To look at a definite example, if we take 1 cubic metre of air at 1 atmosphere pressure and 20C and compress it to 10 atmospheres pressure, its temperature will increase very considerably - to 293C. If we want to store this compressed air at 10 atmospheres pressure and 20C, then more compression will be needed as we cool the gas, or its pressure will drop as its temperature does. The total work done on the gas, and the total heat lost are both about 91.7 Watt-hours (Wh). (This assumes that the air is an ideal diatomic gas.) This gas would now have a lower entropy than the same amount of uncompressed air. The entropy change is 796 J/K (Joules per degree Kelvin). Note the units are energy per degree. This gives a hint of how the entropy change is related to the work that can in principle be extracted from the compressed air. That work can be calculated by multiplying the entropy change by the temperature of the environment in degrees Kelvin. 20C is 293K, so the amount of work that can in principle be extracted is 233 kJ, or 64.8 Wh. If we compare this with the work done compressing the gas, we see that the efficiency of the process is about 71%, even if the compressor is perfectly efficient. Looking at the expansion of the same air back to 1 atmosphere, using a motor to do work in the process, we can work out that the temperature will fall to -121C, and that the work that is done would be 47.5Wh. The efficiency of ths process is thus 47.5/64.8 = 73%, even with a perfect motor. The round-trip efficiency for energy storage and use would then be just 52%. With real compressors and motors it would clearly be considerably worse. These numbers above are for a compression ratio of 10. If we instead use a compression ratio of 100, things get worse still, with a round-trip efficiency of 27%. This actually gives a clue as to how to improve the situation. The maximum efficiency of the cycle depends on the pressure ratio, and rises to 100% as that ratio approaches 1. The answer is to use staged compression, with cooling back to ambient temperature between the stages, and staged expansion, with reheat back to ambient temperature between stages. If we get the 100 times compression by two stages of times 10 each, then half the work goes into the first stage and half into the second, with efficiencies as for 10 times compression - a huge improvement. If we use four stages (ratio 3.17), then the maximum effficiency would be 72%. If we take into account that real compressors and engines are not perfect, and neither are coolers and reheaters, we can see that real overall efficiencies achieved are never likely to be very good, even with very complicated equipment
  13. This thread is not about mornings or any other specific time of the day!
  14. VERY inefficient way of storing energy. You are basically throwing 50-75% of the energy away.
  15. Nice informative presentation. Richard Dawkins is a bit of a nutter. He is more fanatic than the religious fanatics he is trying to disprove. I think he has totally missed the point that religion to many just is a social "feel good" thing they enjoy while singing a few songs together with other people.