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INTRODUCTION [J-B, Ressource Humaine] Oufffffff ! J'ai besoin d'être éclairée, là ! C'est du premier degré ? de l'humour noir ? du cynisme ?[N-T] Qu'est-ce qui vous choc dans l'humour ou le…
Un couplage de géants:
In a coupling of giants recently, the 2.5-megawatt dynamometer at the U.S. Department of Energy's National Renewable Energy Laboratory blasted 12.6 million inch pounds of torque at Samsung's 185,000-pound wind turbine drive train.
The King Kong of wind turbines battled the Godzilla of dynamometers to a draw.
It was the greatest amount of power ever measured at NREL's dynamometer lab, and the largest full-scale dynamometer test of a wind turbine drive train ever done in the United States.
Samsung officials wanted to learn how well their 250-foot-high wind turbines would survive 25 years of gales, gusts, rain, rust, cyclones and dust.
They turned to NREL because its dynamometer can simulate worst-case wind conditions 24 hours a day. In a few months of testing, a manufacturer can learn whether its gear boxes, bearings and cog wheels will stand up to real-world conditions.
NREL's 2.5-megawatt dynamometer is outfitted with a powerful 3,550-horsepower electric motor coupled to a three-stage epicyclic gearbox. The motor can produce speeds up to 30 revolutions per minute, simulating everything from soft breezes to backbreaking gales.
Decades of Data in Two Months of Testing
"If we tried to get this information out in the field, it would take years to acquire this kind of data," Ed Overly, master research technician and dynamometer gatekeeper at NREL's National Wind Technology Center (NWTC), said. "We run the turbine under test conditions for 24 hours a day, seven days a week at 2.1 megawatts. We can monitor how all the fluid and bearing temperatures equilibrate at their maximum points. We see how well the inverter operates under different load conditions to detect if there are any unknown faults."
"Doing this test with Samsung has given us the experience of testing a very large machine at the Dynamometer Facility, which we've never done before," Overly said.
Samsung already has a similar sized (2.5-megawatt) wind turbine running in Lubbock, Texas, that can provide electricity for 1,800 homes, said In-kyu Kim, manager of the Wind Turbine Development team at Samsung. But the company had never tested one of its turbines above 600 kilowatts.
Rocketing from zero to 75 mph in 3.766 seconds, the University of Michigan's MRacing Formula SAE team set an SAE Collegiate Design Series record in acceleration at the event held at Michigan International Speedway May 12-15.
Racing against 120 teams from universities and colleges across the globe, the team had its best finish in 16 years. The Michigan team took second overall in the competition.
"It was very exciting," said project manager and driver Katherine Lapham, a senior mechanical engineering student. "Our goal was to finish in the top five this year and we were aiming for top three. The top teams from Europe did come to the Michigan event this year."
MRacing won first in the GM Acceleration Award, the FEV Powertrain Development Award and the Joe Gibbs Spirit of Innovation Award; and second in the Honda R&D Americas Inc Dynamic Event Award and the GM Endurance Award. The Gibbs award recognizes a simulation that Sumeet Rai, a senior mechanical engineering student, has performed over the past few years.
This was the first of two international competitions the team participates in every year. The next is in Germany, Aug. 4-8.
Provided by University of Michigan (news : web)
More information: MRacing - http://mracing.engin.umich.edu/home.htm
Je pofite de cet article très intéressant pour vous faire connaitre l'adresse "sous pression" très riche en informations sur la fonderie et les matériaux associés.
Spherical tank dome (NASA) was manufactured from a flat plate "blank" made of the 2195 alloy
Aluminium-Lithium
Pour habiller ce petit bijou de technologie, construit par Lockheed Martin dans le cadre du programme Constellation de la NASA, les Américains ont choisi des alliages de faible densité en aluminium-lithium. Un mariage de métaux, super léger, robuste, rigide… Bref, tout ce qu’il faut pour assurer la sécurité des astronautes.
Un petit pied de nez, au passage, aux matériaux composites qui ont encore besoin de faire leurs preuves dans l’aérospatiale.
L’un des ces alliages (le 2195, précisément) est produit dans les usines de Montreuil-Juigné (Maine-et-Loire) et d’Issoire (Puy de Dôme). Les premières livraisons commenceront «
prochainement ». Un très joli coup pour ces installations et de belles perspectives d’avenir
Le lithium
Masse volumique : 534 kg/m3
Température de fusion : 180°C
Chaleur massique : 3582 J/kg.K (la plus importante de tous les métaux)
Conductivité thermique : 84.7 W/m.K
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