Bubble Fusion Research Articles

Bubble fusion scientist disciplined

Bubble fusion scientist disciplined

Bubble fusion researcher punished for misconduct

Bubble fusion researcher punished for misconduct

Bubble-fusion researcher loses misconduct appeal

Bubble-fusion researcher loses misconduct appeal

Bubble fusion discoverer says his science is vindicated

Bubble fusion discoverer says his science is vindicated

Modeling, analysis and prediction of neutron emission spectra from acoustic cavitation bubble fusion experiments

Self-nucleated and external neutron nucleated acoustic (bubble fusion) cavitation experiments have been modeled and analyzed for neutron spectral characteristics at the detector locations for all separate successful published bubble fusion studies. Our predictive approach was first calibrated and validated against the measured neutron spectrum emitted from a spontaneous fission source ( 252Cf), from a Pu–Be source and from an accelerator-based monoenergetic 14.1 MeV neutrons, respectively. Three-dimensional Monte-Carlo neutron transport calculations of 2.45 MeV neutrons from imploding bubbles were conducted, using the well-known MCNP5 transport code, for the published original experimental studies of Taleyarkhan et al. [Taleyarkhan, et al., 2002. Science 295, 1868; Taleyarkhan, et al., 2004. Phys. Rev. E 69, 036109; Taleyarkhan, et al., 2006a. PRL 96, 034301; Taleyarkhan, et al., 2006b. PRL 97, 149404] as also the successful confirmation studies of Xu et al. [Xu, Y., et al., 2005. Nuclear Eng. Des. 235, 1317–1324], Forringer et al. [Forringer, E., et al., 2006a. Transaction on American Nuclear Society Conference, vol. 95, Albuquerque, NM, USA, November 15, 2006, p. 736; Forringer, E., et al., 2006b. Proceedings of the International Conference on Fusion Energy, Albuquerque, NM, USA, November 14, 2006] and Bugg [Bugg, W., 2006. Report on Activities on June 2006 Visit, Report to Purdue University, June 9, 2006]. NE-213 liquid scintillation (LS) detector response was calculated using the SCINFUL code. These were cross-checked using a separate independent approach involving weighting and convoluting MCNP5 predictions with published experimentally measured NE-213 detector neutron response curves for monoenergetic neutrons at various energies. The impact of neutron pulse-pileup during bubble fusion was verified and estimated with pulsed neutron generator based experiments and first-principle calculations. Results of modeling-cum-experimentation were found to be consistent with published experimentally observed neutron spectra for 2.45 MeV neutron emissions during acoustic cavitation (bubble) fusion experimental conditions with and without ice-pack (thermal) shielding. Calculated neutron spectra with the inclusion of ice-pack shielding are consistent with the published spectra from experiments of Taleyarkhan et al. [Taleyarkhan, et al., 2006a. PRL 96, 034301] and Xu et al. [Xu, Y., et al., 2005. Nuclear Eng. Des. 235, 1317–1324] where ice-pack shielding was present, whereas without ice-pack shielding the calculated neutron spectrum is consistent with the experimentally observed neutron spectra of Taleyarkhan et al. [Taleyarkhan, et al., 2002. Science 295, 1868; Taleyarkhan, et al., 2004. Phys. Rev. E 69, 036109] and Forringer et al. [Forringer, E., et al., 2006a. Transaction on American Nuclear Society Conference, vol. 95, Albuquerque, NM, USA, November 15, 2006, p. 736; Forringer, E., et al., 2006b. Proceedings of the International Conference on Fusion Energy, Albuquerque, NM, USA, November 14, 2006] and also that from GEANT computer code [Agostinelli, S., et al., 2003. Nuclear Instrum. Methods Phys. Res. A 506, 250–303] predictions [Naranjo, B., 2006. PRL 97 (October), 149403] in which ice shielding was also absent. The results of this archive confirm for the record that the confusion and controversies caused from past reports [Reich, E., 2006. Nature (March) 060306. news@nature.com; Naranjo, B., 2006. PRL, 97 (October) 149403] have resulted from their neglect of important details of bubble fusion experiments. Results from this paper demonstrate that ice-pack shielding between the detector and the fusion neutron source, gamma photon leakage and neutron pulse-pileup due to picosecond duration neutron pulse emission effects play important roles in affecting the spectra of neutrons from acoustic inertial confinement thermonuclear fusion experiments.

Bubble-fusion engineer sues other scientists

Bubble-fusion engineer sues other scientists

Bubble-fusion allegations merit more investigation

Bubble-fusion allegations merit more investigation

Congress requests bubble-fusion reports

Congress requests bubble-fusion reports

Bubble Fusion Researcher Cleared of Misconduct Charges, but Doubts Linger

Bubble Fusion Researcher Cleared of Misconduct Charges, but Doubts Linger

Disputed inquiry clears bubble-fusion engineer

Purdue's investigation fails to satisfy critics.

Attempts to observe bubble fusion in deuterated acetone

A pulsed neutron generator (PNG) and a radioactive source have been used to seed cavitation at dynamic pressures ranging up to 35 atm. No fusion signal above background has been observed. Our upper bound is less than 1E−4 of the signal claimed by R. P. Taleyarkhan et al. [Phys. Rev. Lett. 96, (2006)]. Reasons for the failure of bubble fusion in acetone and future directions will be discussed. [Research funded by DARPA. We thank Brian Kappus for valuable discussions.]

Purdue Completes Review of Bubble Fusion Researcher

Purdue Completes Review of Bubble Fusion Researcher

Bubble Fusion Research Under Scrutiny

This paper reports on the controversy surrounding a new method of achieving fusion by imploding bubbles in a liquid. Called bubble fusion or sonofusion, it was discovered by a team of researchers led by Purdue University professor, Rusi P. Taleyarkhan. While many experts believe that making hydrogen nuclei fuse in imploding bubbles is possible in principle, they are not convinced that this was actually achieved by Taleyarkhan. They are concerned whether Taleyarkhan's group has ruled out possible sources of errors in detecting the neurons that are characteristic fusion signature. So far, no independent group has been able to replicate the experiment

Bubble fusion: silencing the hype

Bubble fusion: silencing the hype

Evidence for bubble fusion called into question

Evidence for bubble fusion called into question

Nuclear Emissions During Self-Nucleated Acoustic Cavitation

A unique, new stand-alone acoustic inertial confinement nuclear fusion test device was successfully tested. Experiments using four different liquid types were conducted in which bubbles were self-nucleated without the use of external neutrons. Four independent detection systems were used (i.e., a neutron track plastic detector to provide unambiguous visible records for fast neutrons, a detector, a NE-113-type liquid scintillation detector, and a NaI gamma ray detector). Statistically significant nuclear emissions were observed for deuterated benzene and acetone mixtures but not for heavy water. The measured neutron energy was <or=2.45 MeV, which is indicative of deuterium-deuterium (D-D) fusion. Neutron emission rates were in the range approximately 5x10(3) n/s to approximately 10(4) n/s and followed the inverse law dependence with distance. Control experiments did not result in statistically significant neutron or gamma ray emissions.

Theory of supercompression of vapor bubbles and nanoscale thermonuclear fusion

This paper provides the theoretical basis for energetic vapor bubble implosions induced by a standing acoustic wave. Its primary goal is to describe, explain, and demonstrate the plausibility of the experimental observations by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] of thermonuclear fusion for imploding cavitation bubbles in chilled deuterated acetone. A detailed description and analysis of these data, including a resolution of the criticisms that have been raised, together with some preliminary HYDRO code simulations, has been given by Nigmatulin et al. [Vestnik ANRB (Ufa, Russia) 4, 3 (2002); J. Power Energy 218-A, 345 (2004)] and Lahey et al. [Adv. Heat Transfer (to be published)]. In this paper a hydrodynamic shock (i.e., HYDRO) code model of the spherically symmetric motion for a vapor bubble in an acoustically forced liquid is presented. This model describes cavitation bubble cluster growth during the expansion period, followed by a violent implosion during the compression period of the acoustic cycle. There are two stages of the bubble dynamics process. The first, low Mach number stage, comprises almost all the time of the acoustic cycle. During this stage, the radial velocities are much less than the sound speeds in the vapor and liquid, the vapor pressure is very close to uniform, and the liquid is practically incompressible. This process is characterized by the inertia of the liquid, heat conduction, and the evaporation or condensation of the vapor. The second, very short, high Mach number stage is when the radial velocities are the same order, or higher, than the sound speeds in the vapor and liquid. In this stage high temperatures, pressures, and densities of the vapor and liquid take place. The model presented herein has realistic equations of state for the compressible liquid and vapor phases, and accounts for nonequilibrium evaporation/condensation kinetics at the liquid/vapor interface. There are interacting shock waves in both phases, which converge toward and reflect from the center of the bubble, causing dissociation, ionization, and other related plasma physics phenomena during the final stage of bubble collapse. For a vapor bubble in a deuterated organic liquid (e.g., acetone), during the final stage of collapse there is a nanoscale region (diameter ∼100nm) near the center of the bubble in which, for a fraction of a picosecond, the temperatures and densities are extremely high (∼108K and ∼10g∕cm3, respectively) such that thermonuclear fusion may take place. To quantify this, the kinetics of the local deuterium/deuterium (D∕D) nuclear fusion reactions was used in the HYDRO code to determine the intensity of the fusion reactions. Numerical HYDRO code simulations of the bubble implosion process have been carried out for the experimental conditions used by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] at Oak Ridge National Laboratory. The results show good agreement with the experimental data on bubble fusion that was measured in chilled deuterated acetone.

Bubble power [other sources of nuclear energy

Research teams from various organizations have joined forces to create the Acoustic Fusion Technology Energy Consortium (AFTEC) to promote the development of sonofusion and its related science and technology. Technically known as acoustic inertial confinement fusion, sonofusion was derived from a related phenomenon, sonoluminescence. Sonofusion involves the application of sound waves to a deuterium-rich liquid to create pressure oscillations that implode tiny bubbles filled with deuterium vapor. The bubbles' violent collapse can cause some of the deuterium nuclei to undergo fusion. Fusion produced no greenhouse gases and, unlike conventional nuclear fission reactors, it produces no noxious radioactive wastes that last for thousands of years. Much more extensive research, however, is required before it is clear whether sonofusion can become a new energy source.

Solid evidence for bubble fusion?

Solid evidence for bubble fusion?

Evidence for nuclear emissions during acoustic cavitation revisited

This paper extends the experimental and numerical results presented previously and addresses the major criticisms raised. In addition, the most recent results are discussed. In acoustic cavitation experiments with chilled (ɛ0 °C) deuterated acetone (C3D6O), the production of tritium and 2.45 MeV neutrons [which are characteristic of deuterium-deuterium (D-D) fusion] was observed during vapour bubble implosions in an acoustic pressure field. Similar experiments with deuterated acetone at room temperature (ɛ20 °C) and control experiments with normal acetone (C3H6O), at both 0 and 20 °C, showed no statistically significant increases in either tritium level or neutron emissions. Numerical simulations of the processes that account for the shock waves generated in the liquid and within the collapsing bubbles supported these experimental observations and showed that high densities and temperatures (° 108 K) may be achieved during bubble cloud implosions, yielding the conditions required for D-D nuclear fusion reactions. The present paper treats the bubble fusion experiments and theoretical results in greater detail than was possible in the previous publications, contains some refinements, addresses some important questions raised by reviewers and critics and discusses possible applications of this interesting phenomenon.