SCIENCE

With a powerful laser blast, scientists near a nuclear fusion milestone

A National Ignition Facility experiment produced a record 1.3 million joules of fusion energy.

laser blast in a nuclear fusion experiment

With a powerful laser zap, scientists have blasted toward a milestone for nuclear fusion.

A fusion experiment at the world’s biggest laser facility released 1.3 million joules of energy, coming close to a break-even point known as ignition, where fusion begins to release more energy than required to detonate it. Reaching ignition would strengthen hopes that fusion could one day serve as a clean, plentiful energy source, a goal that scientists have struggled to make progress toward (SN: 2/8/18).

By pummeling a tiny capsule with lasers at the National Ignition Facility, or NIF, at Lawrence Livermore National Laboratory in California, scientists triggered fusion reactions that churned out more than 10 quadrillion watts of power over 100 trillionths of a second. In all, the experiment, performed on August 8, released about 70 percent of the energy of the laser light used to set off the fusion reactions, putting the facility much closer to ignition than ever before.

Notably, because the capsule absorbs only a portion of the total laser energy focused on it, the reactions actually produced more energy than directly went into igniting them. “That, just fundamentally, is a truly amazing feat,” says plasma physicist Carolyn Kuranz of the University of Michigan in Ann Arbor, who was not involved with the research. By that metric, the fusion reactions produced about five times as much energy as was absorbed.

“It’s a really exciting result, and it wasn’t clear that NIF would be able to get to this result,” Kuranz says. For years, NIF scientists have strived to reach ignition, but they have been plagued with setbacks (SN: 4/4/13). While the new results have yet to be published in a scientific journal, NIF scientists went public with their discovery after word got out to the scientific community and excitement mounted.

“It makes me very hopeful … for fusion in the future,” Kuranz says.

Nuclear fusion, the same process that powers the sun, would be an appealing source of energy on Earth because it checks several boxes for environmental friendliness: It wouldn’t generate climate-warming greenhouse gases or dangerous, long-lived radioactive waste. In nuclear fusion, hydrogen nuclei meld together to form helium, releasing energy in the process. But fusion requires extreme temperatures and pressures, making it difficult to control.

NIF is not alone in the fusion quest. Other projects, such as ITER, an enormous facility under construction in southern France, are using different techniques to tackle the problem (SN: 1/27/16). But those efforts have also met with difficulties. Perhaps unsurprisingly, controlling reactions akin to those in the sun is challenging no matter how you go about it.

In NIF’s fusion experiments, 192 laser beams converge on a small cylinder containing a peppercorn-sized fuel capsule. When that powerful laser burst hits the cylinder, X-rays stream out, vaporizing the capsule’s exterior and imploding the fuel within. That fuel is a mixture of deuterium and tritium, varieties of hydrogen that respectively contain one or two neutrons in their atomic nuclei. As the fuel implodes, it reaches the extreme densities, temperatures and pressures needed to fuse the hydrogen into helium. That helium can further heat the rest of the fuel, what’s known as alpha heating, setting off a fusion chain reaction.

That last step is crucial to boosting the energy yield. “What’s new about this experiment is that we’ve created a system in which the alpha heating rate is far larger than we’ve ever achieved before,” says NIF physicist Arthur Pak.

Scientists navigated a variety of quagmires to get to this stage. “There’s a whole a host of physics issues … that we’ve faced off and mitigated,” Pak says. For example, researchers took pains to make the capsule absorb more energy, to eliminate tiny defects in the capsule and to carefully tune the laser pulses to maximize fusion.

In 2018, researchers began seeing the payoff of those efforts. NIF achieved a then-record fusion energy of 55,000 joules. Then, in spring 2021, NIF reached 170,000 joules. Further tweaking the design of the experiment, scientists suspected, could increase the output even more. But the new experiment went beyond expectations, producing nearly eight times the energy of the previous effort.

Further studies will help NIF scientists determine exactly how their changes created such bountiful energy and how to enhance the output further. Still, even if NIF achieves full-fledged ignition, using fusion to generate power for practical purposes is still a long way off. “There will be a huge amount of work needed to turn the technology into a viable source of energy,” says laser plasma physicist Stuart Mangles of Imperial College London, who was not involved with the research. “Nevertheless, this is a really important milestone on the way.”

Questions or comments on this article? E-mail us at feedback@sciencenews.org

CITATIONS

Lawrence Livermore National Laboratory. National Ignition Facility experiment puts researchers at threshold of fusion ignition. Published August 18, 2021.

Source:https://www.sciencenews.org/

Creating awareness of bright future in welding industry

source:engmag.in

Creating awareness of bright future in welding industry

Mr. Vishwanath V. Kamath – Managing Director , Fronius India Private Limited.

Q. As a prominent player in the welding space, what trends and innovations are you observing that will continue to shape the future of the welding

The welding or, joining technologies are fundamental to manufacturing. There has been a great broadening of process types for joining of metals over the last 40 years, and therefore the range of products available. From conventional forms of arc welding to cold metal transfer(CMT), CMT-Twin, CMT Advanced, high performance welding processes like laser hybrid-Twin, Twin Wire tandem welding, Aluminum spot welding (DeltaSpot) etc. techniques have been added, to increase the range of materials to be joined, the strength and aspect ratio of the joint, the speed of joining, the reduction in any collateral damage etc.

Power sources has become smart and intelligent to face various challenges in welding and provide the complete process solution through high Speed communication and by processing a huge amount of data in the shortest possible time. The future trend of welding sector is hidden in the challenges the manufacturing industry is facing today- like environmental sustainability including the global warming, development of newer alloys towards light weighting and the inherent difficulties in joining technologies owing to thin and light weight material joining techniques. Innovations trend in welding in the coming future will be focussed towards the development of advanced technologies for joining Al, Al alloys and High strength steels, without much of the post welding operations by adopting to low heat high performance welding techniques.

Q. How are technology trends like robotics and automation influencing the welding industry?

Robotics have become much more popular in the last 20 years as they can significantly reduce labour costs and operate in hazardous environments such as welding. Automotive sector has been the key driving force for the robotics market which is growing steadily over last 2 decades. We must mention that the understanding and opinion of this sector has seen a sea change –conventionally this segment used to believe that robot is the saviour and welding machine was never given the due attention. But over the years the manufacturing sector has understood well that the key performer in robotic welding is the welding technology adopted and the easy integration of the robot with the welding system for seamless communication and possibilities.

Welding Automation though aspire to grow faster but due to the input material inconsistency and need for the high initial capital investment, has put this on a slow track. Another bigger opportunity / challenges is lack of integrators for providing high precision welding automation solutions. To catch up with the growing demand of robotics and automation for welding, welding fraternity must come forward to share and upgrade integrators with welding knowledge to rise them to the level of total solution provider.

Q. What kind of opportunities are you expecting from International Congress 2020 (IC2020) being organized by The Indian Institute of Welding?

International Congress 2020 (IC2020) is a global platform for welding companies to showcase the latest developments in the field of welding. The event is attended by welding enthusiasts from across the country and people from all segments of manufacturing industry. Fronius is known for its strong research & development (R&D) and product development. There will be two international paper presentation in the IC 2020 from Fronius International GmbH.

Q. What products do you plan to showcase at IC2020?

We may showcase our latest technologies and developments in light weight material joining technologies and some high performance technologies for metal fabrication industry. Fronius India showcase the latest developments and new products for high performance welding and welding automation and robotic solutions to the Indian Industry and delegates.

Q. Comment on the challenges and opportunities in Indian welding industry?

The most common challenges is the perception of the young generation about this industry. There is huge number of young workforce getting ready to join industry but very few of them wants to join welding or, metal fabrication industry as they are lured by the comfort and glare of the IT and other so called white collar job. This is leading to a huge manpower and skilled man power shortage in the manufacturing especially welding industry. Welding Industry must work on improving the impression and attracting the young generations to join this sector. This can be done by adopting latest technologies as the new generation is going to be tech savvy. Welding stalwarts’ must take the time out and reach out to the institutions to share their experiences and life story as a welding professionals.

Q. Comment on the present status of the Indian Welding sector vis- à-vis global peers.

Indian welding sector has huge opportunities for growth as the global majors are eying India as the most safe, profitable and reliable destination for manufacturing & investment. Govt policies like “Make in India”, “Skill India” has undoubtedly have given required impetus to this sector. In order to reduce cost of welding products many has started adopting cheaper products, techniques but in long remained vulnerable. Where the global welding industry is looking at the Total Cost of Production (TCoP) but Indian industry is still considering the ownership cost overlooking the total cost of operation.

Q. What are the future growth prospects and opportunities in welding in India?

Joining of metals would remain important for all sectors of the industry as metals like steel and aluminium etc. are needed in every sectors be it infrastructure, heavy engineering, automotive, defence and aerospace etc. As Indian GDP growth rate, even after the slowdown, remains among the toppers globally, India will continue to remain the preferred destination for foreign investors. This will keep boosting the manufacturing sector and definitely welding industry as well. Productivity, profitability and sustainable growth will be key factors for the survival of any industry in this volatile market. Adoption of advanced welding knowledge, technology, skill and optimization of overall cost of production will be key to success.