Search found 207 results
- 25/04/24, 11:24
- Forum : Economy and finance, sustainability, growth, GDP, ecological tax systems
- Subject : The Wonderful World of the European Union: 100 km/h motorways everywhere in the EU?
- answers: 62
- views: 1344
Re: The Wonderful World of the European Union: 100 km/h motorways everywhere in the EU?
https://www.onisr.securite-routiere.gouv.fr/sites/default/files/2024-01/2024%2001%2031_ONISR_Accidentalit%C3%A9_Bilan_provisoire_2023%2017h25.pdf I.1. Tendances 2023 sur les réseaux routiers en France métropolitaine Les routes hors agglomération enregistrent 59 % des décès et 48 % des blessés grave...
- 30/03/24, 12:43
- Forum : Science and Technology
- Subject : “Chinese” electric chainsaws and delimbers: what are they worth?
- answers: 213
- views: 7400
Re: “Chinese” electric chainsaws and delimbers: what are they worth?
The performance of a hydraulic device depends on its application: at low speed and in linear movement, it is interesting, in rapid rotation it is very mediocre, but is justified in certain assemblies for the flexibility that it allows. In short, a matter of compromise depending on the objectives...
- 30/03/24, 12:19
- Forum : Science and Technology
- Subject : “Chinese” electric chainsaws and delimbers: what are they worth?
- answers: 213
- views: 7400
Re: “Chinese” electric chainsaws and delimbers: what are they worth?
Exactly and many cars use the brilliant torque converter system...which is nothing other than a compacted hydraulic pump-motor...if the efficiency was so poor it would not be used in automobiles.. .In this regard, I came across a Chrysler advert which presented...
- 30/03/24, 10:30
- Forum : Science and Technology
- Subject : “Chinese” electric chainsaws and delimbers: what are they worth?
- answers: 213
- views: 7400
Re: “Chinese” electric chainsaws and delimbers: what are they worth?
The performance of a hydraulic device depends on its application: at low speed and in linear movement, it is interesting, in rapid rotation it is very mediocre, but is justified in certain assemblies for the flexibility that it allows. In short, a matter of compromise depending on the objectives...
- 24/03/24, 11:01
- Forum : electric transport: cars, bicycles, public transport, planes ...
- Subject : Driving an electric car every day
- answers: 532
- views: 47953
Re: Driving an electric car every day
Certainly, but the almost majority of all families with 2 working parents have 2 or more cars...ask Macro!!! :mrgreen: Besides, most people who switched to electric kept a thermal "as a backup"... In the USA perhaps, but in France and Western Europe...
- 22/02/24, 10:32
- Forum : Electricity, electronics and IT Hi-Tech, Internet, DIY, lighting, materials and new
- Subject : Leroy Sommer direct current hydroelectric generator
- answers: 42
- views: 3101
Re: Leroy Sommer based hydroelectric generator with direct current
The most efficient turbine at low altitude is the Archimedes screw, which can be produced inexpensively with the means at hand... I have some doubts about the lifespan of the machine... It was for quick demo, some youtubers make crates of it, show him the essentials. He didn't...
- 04/02/24, 23:25
- Forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
- Subject : How to properly design a VTOL/ADAV helicopter-plane?
- answers: 153
- views: 25481
Re: How to properly design a VTOL/ADAV aircraft-helicopter?
Except the V 22 Osprey and its cousins. Ah, that’s why the V22 prototypes killed so many people, you think? Which cousins?? I do not know anymore ! These are not the kind of clearly identified flying objects that excite me the most... There were several prototypes in the 70s and 80s, before...
- 04/02/24, 18:43
- Forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
- Subject : How to properly design a VTOL/ADAV helicopter-plane?
- answers: 153
- views: 25481
Re: How to properly design a VTOL/ADAV aircraft-helicopter?
Oh yes, I didn't know either! THANKS ! It looks like it had a small load-bearing wing...too bad it was blown away by the rotors... https://fr.wikipedia.org/wiki/Mil_Mi-12 A monster that only the Soviets knew how to make! 4 turbine engines but only 2 rotors? They shouldn't have...
- 04/02/24, 17:24
- Forum : New transport: innovations, engines, pollution, technologies, policies, organization ...
- Subject : How to properly design a VTOL/ADAV helicopter-plane?
- answers: 153
- views: 25481
Re: How to properly design a VTOL/ADAV aircraft-helicopter?
So why did you abandon this promising configuration (which would have been even more so with a small supporting wing apart from the wind of the rotors...) in favor of single rotors with anti-torque? Apart from the footprint and certainly less maneuverability in switchbacks...I don't see...
- 04/02/24, 16:06
- Forum : Hydraulic, wind, geothermal, marine energy, biogas ...
- Subject : PV in China: impressive!
- answers: 13
- views: 1487
Re: PV in China: impressive!
I don't have the exact figures for China. China, around 7 TWhe/year or 000 kWhe/inhabitant, including around 5 from PV sources. Europe (EU000), 600 TWhe/year, or 27 kWhe/inhabitant, of which approximately 2. Germany, 690 TWhe/year, or 6 kWhe/inhabitant, including a total of nearly 000 kWhe/inhabitant. France, 400 TWhe/...