Citation: Researcher sees potential in generating energy from vibrations (2019, March 8) retrieved 17 July 2019 from https://phys.org/news/2019-03-potential-energy-vibrations.html As an aerospace engineer who specializes in designing structures to avoid destructive vibrations, it was only natural for Levin to approach the quest for sustainable energy by applying what he knows about flutter and limit cycle oscillations, or LCO. Because of its potential to cause structural failure, flutter is nearly always engineered out of structures. “Usually flutter is not desirable,” said Levin. “But sometimes violent flutter can turn into moderate LCO, which will cause no failure, and this can be useful.” Levin wanted to explore the potential of harnessing the energy generated by flutter, and he took a six-month detour from his dissertation work, with the support of his advisor.Levin set up an experiment in the aeroelasticity lab’s wind tunnel, using a thin aluminum plate and piezoelectric elements, which generate voltage in response to mechanical stressors like flutter. He found that by increasing the vibrations’ frequency and amplitude, creating more curvature in the vibrational motion, using efficient piezoelectric elements and reducing air speed, he could squeeze the most power from the motion of the plate—sometimes increasing efficiency by more than 200 percent. Are large-scale flutter farms in our future? Probably not, said Levin. “My vision for this is, maybe you go on a long hike, on a cloudy day. You don’t have any solar power to charge your phone. But you do have a folded generator in your bag that you can take out, let it catch the breeze as you hike, and it can charge your phone. You can go even further and combine solar and wind. It’s scalable and useful. And,” he added jokingly, “it doesn’t involve scary mathematics. We’re using something that is so simple and so basic—at least for an aerospace engineer.”Levin will present his project, titled “Improving Piezoelectric Energy Harvesting from an Aeroelastic System,” at the International Forum on Aeroelasticity and Structural Dynamics in Savannah, Georgia in June of 2019. Provided by Duke University This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. Credit: Duke University “Everyone is trying to get free energy—from the wind, from the waves, from the sun,” said Dani Levin, a Duke MEMS Ph.D. student in the lab of Professor Earl Dowell. Scientists harvest energy from beam’s self-induced, self-sustaining vibrations in airflow Explore further
Analysis of the flight recorders of the crashed Ethiopian Airlines plane has begun, the airline said Friday, and The New York Times reported that the pilot requested permission “in a panicky voice” to return to the airport shortly after takeoff as the plane dipped up and down sharply and appeared to gain startling speed. © 2019 The Associated Press. All rights reserved. Investigators looking into the Indonesian crash are examining whether the software automatically pushed the plane’s nose down repeatedly, and whether the Lion Air pilots knew how to solve that problem. Ethiopian Airlines says its pilots received special training on the software.At the crash site in Hejere, about 50 kilometers (31 miles) from Addis Ababa, searchers continued to pick through the debris. Blue plastic sheeting covered the wreckage of the plane. Students from an elementary school walked an hour and a half to the site to pay respects.Anxious family members began giving DNA samples and waited for news on the identification of remains. Members of Israel’s ZAKA emergency response team were granted access to the site for forensic work.Canada’s ambassador to Ethiopia, Antione Chevrier, told The Associated Press that discussions on repatriating remains would begin once the identification process begins to yield results. “The next steps will take some time,” he said. Canada lost 18 people.”We are not told what they have found so far,” Ethiopian citizen Faysal Hussein, whose cousin was killed, told the AP. “We are sitting here like forever. We were taken to the crash site on Wednesday but not allowed to get a closer look.”One relative collected soil in a plastic bag, perhaps for lack of anything else .A Kenyan citizen, Pauline Gathu, lost a brother. Thirty-two Kenyans were killed.”We were expecting that we will have our body well-kept but we are amazed to hear that there is nothing, totally nothing,” she said. “And people are waiting for us to give them reports of what we have found but we don’t have words, we don’t know what to do.” Ethiopian relatives of crash victims mourn and grieve at the scene where the Ethiopian Airlines Boeing 737 Max 8 crashed shortly after takeoff on Sunday killing all 157 on board, near Bishoftu, south-east of Addis Ababa, in Ethiopia Thursday, March 14, 2019. About 200 family members of people who died on the crashed jet stormed out of a briefing with Ethiopian Airlines officials in Addis Ababa on Thursday, complaining that the airline has not given them adequate information. (AP Photo/Mulugeta Ayene) Ethiopian Airlines crash: What is the MCAS system on the Boeing 737 Max 8? Citation: Ethiopian Airlines says analysis of flight recorders begins (2019, March 15) retrieved 17 July 2019 from https://phys.org/news/2019-03-ethiopian-airlines-analysis-flight.html The Max is the latest upgrade to the Boeing 737s. Because its engines are larger and heavier, they are placed higher and farther forward on the wings. That created concern that the plane might be slightly more prone to an aerodynamic stall if not flown properly, so Boeing developed software to prevent that. The report cited “a person who reviewed air traffic communications” from Sunday’s flight saying controllers noticed the plane was moving up and down by hundreds of feet.An airline spokesman has said the pilot was given permission to return. But the plane crashed minutes later outside Addis Ababa, killing all 157 on board.French authorities now have the plane’s flight data and voice recorders for analysis. They have said it was unclear whether data could be retrieved. The data recorder appeared to show damage. Ethiopian Airlines said an Ethiopian delegation led by its chief accident investigator had arrived in Paris.In Ethiopia, officials started taking DNA samples from victims’ family members to assist in identifying remains. The dead came from 35 countries.Countries including the United States have grounded the Boeing 737 Max 8 as the U.S.-based company faces the challenge of proving the jets are safe to fly amid suspicions that faulty software might have contributed to two crashes that killed 346 people in less than six months.The decision to send the flight recorders to France was seen as a rebuke to the United States, which held out longer than most other countries in grounding the jets. The U.S. National Transportation Safety Board sent three investigators to help French authorities.The U.S. Federal Aviation Administration said regulators had new data from the satellite-based tracking that showed the movements of Ethiopian Airlines Flight 302 were similar to those of Lion Air Flight 610. That flight crashed into the Java Sea off Indonesia in October, killing 189 people.The data show both planes flew with erratic altitude changes that could indicate the pilots struggled to control the aircraft. Both crews tried to return to the airport.Boeing said it supports the grounding of its planes as a precautionary step, while reiterating its “full confidence” in the safety of the 737 Max. Engineers are making changes to the system designed to prevent an aerodynamic stall if sensors detect that the jet’s nose is pointed too high and its speed is too slow.Boeing also announced it had paused delivery of the Max, although the company planned to continue building the jets. This photo provided by by the French air accident investigation authority BEA on Thursday, March 14, 2019, shows one of the black box flight recorder from the crashed Ethiopian Airlines jet, in le Bourget, north of Paris. The French air accident investigation agency has released a photo of the data recorder from the crashed Ethiopian Airlines jet. The agency, known by its French acronym BEA, received the flight’s data recorder and voice recorder Thursday. (BEA via AP) Explore further This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
RELATED SHARE SHARE EMAIL File Photo Published on May 10, 2019 COMMENT Microphones will fall silent and high-octane poll campaigning will end on Friday evening in the national capital as the 48-hour silence period kicks in from 6 pm ahead of the Lok Sabha elections. All seven parliamentary constituencies in Delhi will vote on May 12 as part of the sixth phase of the polls. “The campaigning will end this evening as the 48-hour silence period will kick in at 6 pm today which would stay till 6 pm on Sunday,” Ranbir Singh, Delhi CEO, told reporters. As many as 523 polling locations have been identified till date as critical, he said. “Special paramilitary forces will be deployed there, besides webcasting and CCTV facilities. Micro-observers would also be there. We have made all arrangements for smooth polling,” he said. No campaigning shall be allowed beyond the 6 pm limit, including on social media, Singh said. “All print ads need to be pre-certified for any publication in newspapers,” he added. As many as 164 candidates are in fray in the polls, which are largely been seen as a three-way contest among the BJP, Congress and AAP. COMMENTS political campaigns SHARE The political war goes online
THE spotlight is on the country’s smallest lender, Alliance Bank Malaysia Bhd, which could be looking at paring down its stake in its wholly-owned subsidiary, Alliance Investment Bank Bhd (AIBB).The move, if it materialises, will come amid an extremely competitive time for the investment banking scene both here and globally where it is becoming increasingly difficult to survive without a strong niche.IPO deals have dried up in recent years not only here but regionally while other deal-making activities in Asia have had their worst start to this year since about five years ago due mostly to a global economic slowdown. A source says that advisers have already been hired to start off the process of Alliance Bank selling its majority interest in AIBB. AdChoices广告When asked, Alliance Bank neither confirmed nor denied the matter.Unlock exclusive insights, analyses, and curated news on the economy on The Star Online’s Business section with Starbiz Premium.SubscribeLog In Corporate News13 Jul 2019IJM contract termination likely due to deadline issueCorporate News13 Jul 2019Yinson continues to draw interestProperty13 Jul 2019Pioneering the wellness concept for offices in Malaysia More Stories Tags / Keywords: Economy13 Jul 2019Much to benefit from Malaysia-China tiesBanking12 Jul 2019Fed’s Williams joins with other officials leaning toward rate cutsOil & Gas11 Jul 2019OPEC action and trade truce may give oil the lift it needs Corporate News