Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers Report Bubble Fusion Results Replicated

03.03.2004


Physical Review E publishes paper on fusion experiment conducted with upgraded measurement system



Physical Review E has announced the publication of an article by a team of researchers from Rensselaer Polytechnic Institute (RPI), Purdue University, Oak Ridge National Laboratory (ORNL), and the Russian Academy of Science (RAS) stating that they have replicated and extended previous experimental results that indicated the occurrence of nuclear fusion using a novel approach for plasma confinement.

This approach, called bubble fusion, and the new experimental results are being published in an extensively peer-reviewed article titled “Additional Evidence of Nuclear Emissions During Acoustic Cavitation,” which is scheduled to be posted on Physical Review E’s Web site and published in its journal this month.


The research team used a standing ultrasonic wave to help form and then implode the cavitation bubbles of deuterated acetone vapor. The oscillating sound waves caused the bubbles to expand and then violently collapse, creating strong compression shock waves around and inside the bubbles. Moving at about the speed of sound, the internal shock waves impacted at the center of the bubbles causing very high compression and accompanying temperatures of about 100 million Kelvin.

These new data were taken with an upgraded instrumentation system that allowed data acquisition over a much longer time than was possible in the team’s previous bubble fusion experiments. According to the new data, the observed neutron emission was several orders of magnitude greater than background and had extremely high statistical accuracy. Tritium, which also is produced during the fusion reactions, was measured and the amount produced was found to be consistent with the observed neutron production rate.

Earlier test data, which were reported in Science (Vol. 295, March 2002), indicated that nuclear fusion had occurred, but these data were questioned because they were taken with less precise instrumentation.

“These extensive new experiments have replicated and extended our earlier results and hopefully answer all of the previous questions surrounding our discovery,” said Richard T. Lahey Jr., the Edward E. Hood Professor of Engineering at Rensselaer and the director of the analytical part of the joint research project.

Other fusion techniques, such as those that use strong magnetic fields or lasers to contain the plasma, cannot easily achieve the necessary compression, Lahey said. In the approach to be published in Physical Review E, spherical compression of the plasma was achieved due to the inertia of the liquid surrounding the imploding bubbles.

Professor Lahey also explained that, unlike fission reactors, fusion does not produce a significant amount of radioactive waste products or decay heat. Tritium gas, a radioactive by-product of deuterium-deuterium bubble fusion, is actually a part of the fuel, which can be consumed in deuterium-tritium fusion reactions.

Researchers Rusi Taleyarkhan, Colin West, and Jae-Seon Cho conducted the bubble fusion experiments at ORNL. At Rensselaer and in Russia, Professors Lahey and Robert I. Nigmatulin performed the theoretical analysis of the bubble dynamics and predicted the shock-induced pressures, temperatures, and densities in the imploding vapor bubbles. Robert Block, professor emeritus of nuclear engineering at Rensselaer, helped to design, set up, and calibrate a state-of-the-art neutron and gamma ray detection system for the new experiments.

Special hydrodynamic shock codes have been developed in both Russia and at Rensselaer to support and interpret the ORNL experiments. These computer codes indicated that the peak gas temperatures and densities in the ORNL experiments were sufficiently high to create fusion reactions. Indeed, the theoretical shock code predictions of deuterium-deuterium (D-D) fusion were consistent with the ORNL data.

The research team leaders are all well known authorities in the fields of multiphase flow and heat transfer technology and nuclear engineering. Taleyarkhan, a fellow of the American Nuclear Society (ANS) and the program’s director, held the position of Distinguished Scientist at ORNL, and is currently the Ardent Bement Jr. Professor of Nuclear Engineering at Purdue University. Lahey is a fellow of both the ANS and the American Society of Mechanical Engineers (ASME), and is a member of the National Academy of Engineering (NAE). Nigmatulin is a visiting scholar at Rensselaer, a member of the Russian Duma, and the president of the Bashkortonstan branch of the Russian Academy of Sciences (RAS). Block is a fellow of the ANS and is the longtime director of the Gaerttner Linear Accelerator (LINAC) Laboratory at Rensselaer. The bubble fusion research program was supported by a grant from the Defense Advanced Research Projects Agency (DARPA).

About Rensselaer

Rensselaer Polytechnic Institute, founded in 1824, is the nation’s oldest technological university. The school offers degrees in engineering, the sciences, information technology, architecture, management, and the humanities and social sciences. Institute programs serve undergraduates, graduate students, and working professionals around the world. Rensselaer faculty are known for pre-eminence in research conducted in a wide range of research centers that are characterized by strong industry partnerships. The Institute is especially well known for its success in the transfer of technology from the laboratory to the marketplace so that new discoveries and inventions benefit human life, protect the environment, and strengthen economic development.

Theresa Bourgeois | Rensselaer Polytechnic Institute
Further information:
http://www.rpi.edu/web/News/press_releases/2004/lahey.htm

More articles from Physics and Astronomy:

nachricht Abrupt motion sharpens x-ray pulses
28.07.2017 | Max-Planck-Institut für Kernphysik

nachricht Physicists Design Ultrafocused Pulses
27.07.2017 | Universität Innsbruck

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Abrupt motion sharpens x-ray pulses

Spectrally narrow x-ray pulses may be “sharpened” by purely mechanical means. This sounds surprisingly, but a team of theoretical and experimental physicists developed and realized such a method. It is based on fast motions, precisely synchronized with the pulses, of a target interacting with the x-ray light. Thereby, photons are redistributed within the x-ray pulse to the desired spectral region.

A team of theoretical physicists from the MPI for Nuclear Physics (MPIK) in Heidelberg has developed a novel method to intensify the spectrally broad x-ray...

Im Focus: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

New 3-D imaging reveals how human cell nucleus organizes DNA and chromatin of its genome

28.07.2017 | Health and Medicine

Heavy metals in water meet their match

28.07.2017 | Power and Electrical Engineering

Oestrogen regulates pathological changes of bones via bone lining cells

28.07.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>