Sonoluminescence
description
Transcript of Sonoluminescence
SonoluminescenceSonoluminescence
By:By:Mark CartagineMark Cartagine
OutlineOutline
What Is Sonoluminescence?What Is Sonoluminescence? Sonoluminescence: Process, Features, Sonoluminescence: Process, Features,
PeculiaritiesPeculiarities TheoriesTheories
1.1. ShockwaveShockwave2.2. JetJet
Interesting ResearchInteresting Research
What is Sonoluminescence?What is Sonoluminescence? The EquipmentThe Equipment
ResultResult
Sonoluminescence: ProcessSonoluminescence: Process Bubble trapped between Bubble trapped between
nodes of 25 kHz sound nodes of 25 kHz sound waveswaves
Expands:4Expands:4μμm to 40m to 40μμm m during rarefaction (V↑ x during rarefaction (V↑ x 1000) – near Vacuum1000) – near Vacuum
Collapses to van der Collapses to van der Waals hard core (0.5Waals hard core (0.5μμm) m) during compressionduring compression
VVCollapseCollapse ≈ 1.4 km/s, ≈ 1.4 km/s,
≈ ≈ Mach 4Mach 4
Process Cont’dProcess Cont’d
ReboundReboundaccelaccel ≈ ≈ 10101111gg Bubble Emits Light, Bubble Emits Light,
Sound @ min. radiusSound @ min. radius Light is Broad Light is Broad
SpectrumSpectrum UV>Blue>Red: UV>Blue>Red:
“Equivalent to “Equivalent to 70,000K Plasma”70,000K Plasma”
Sonoluminescence: FeaturesSonoluminescence: Features Flash duration: 50 Flash duration: 50
pico-sec.pico-sec. Interval between Interval between
flashes: 35 millisecflashes: 35 millisec Energy Energy
“Concentration” ~ 10“Concentration” ~ 101212
PeculiaritiesPeculiarities
1.1. Intensity Inversely Intensity Inversely Proportional to Proportional to TemperatureTemperature
2.2. Radius Radius Discontinuity:Discontinuity:
3.3. Works best when Works best when “doped” w/ Noble “doped” w/ Noble Gas (Helium, Argon, Gas (Helium, Argon, Xenon)Xenon)
TheoriesTheories
1.1. ““Shock Wave”Shock Wave”2.2. ““Jet”Jet”
Neither is TotallyNeither is TotallyAcceptedAccepted
““Shock Wave”Shock Wave” Bubble walls collapse Bubble walls collapse
≈≈ Mach 4 Mach 4 Bubble attains hard Bubble attains hard
core radiuscore radius Shock Wave Shock Wave
Continues to Continues to Concentrate EnergyConcentrate Energy
Spherical shock wave Spherical shock wave hits center and hits center and reboundsrebounds
Shock Wave Theory ExplainedShock Wave Theory Explained Combines Adiabatic Heating & Shock Combines Adiabatic Heating & Shock
Wave HeatingWave Heating Ratio of Shockwave Temperatures ~ to Ratio of Shockwave Temperatures ~ to
[Mach No.][Mach No.]22 Mach No. Increases as Walls CollapseMach No. Increases as Walls Collapse Two Shock WavesTwo Shock Waves Ionization OccursIonization Occurs Light Emitted as Electrons Collide w/ IonsLight Emitted as Electrons Collide w/ Ions Max Temp: 3x10Max Temp: 3x1088 K (Theoretical) K (Theoretical)
Theory Strengths, WeaknessesTheory Strengths, WeaknessesExplains:Explains:1.1. Spectrum (Instant Heating)Spectrum (Instant Heating)2.2. Flash Interval, DurationFlash Interval, Duration3.3. Temperature Effect (Vapor Temperature Effect (Vapor ↑ with Temp )↑ with Temp )4.4. Microphones Near Bubble Hear “Pop”Microphones Near Bubble Hear “Pop”Cannot ExplainCannot Explain::1.1. Noble Gas EffectNoble Gas Effect2.2. DiscontinuityDiscontinuity
Critically Dependent on Bubble SymmetryCritically Dependent on Bubble Symmetry
Alternative: “Jet” TheoryAlternative: “Jet” Theory• Bubble “Jitters”Bubble “Jitters”• Asymmetric Asymmetric
CollapseCollapse• Creates “Jet”Creates “Jet”• Propelled toward Propelled toward
Opposite Wall at Opposite Wall at Mach SpeedsMach Speeds
• ““Shattered” Water Shattered” Water Emits Fracto-Emits Fracto-luminescenceluminescence
• Max Temp Max Temp ≈ 10≈ 104 4 KK
Jet Theory Strengths & Jet Theory Strengths & WeaknessesWeaknesses
Explains Explains 1.1. Noble Gas Noble Gas → Disrupts “Crystalline Form”→ Disrupts “Crystalline Form”2.2. Temperature RelationTemperature Relation: : Lower Temps Lower Temps → More → More
Hydrogen Bonds → Greater Water RigidityHydrogen Bonds → Greater Water RigidityCannot ExplainCannot Explain 1.1. DiscontinuityDiscontinuity2.2. SpectrumSpectrum
Models Noble Gas Effect as Random ProcessModels Noble Gas Effect as Random Process
Interesting ResearchInteresting Research
Taleyarkhan et al., 2002Taleyarkhan et al., 2002 Used Used Deuterated Acetone (C3D6O) Injected Neutrons into Bubble @ max Injected Neutrons into Bubble @ max
RadiusRadiusClaims:Claims: Temps Temps ≈ 10≈ 1077 K K Production of Tritium Nucleus + ProtonProduction of Tritium Nucleus + Proton Helium-3 Nucleus + 2.45 MeV NeutronHelium-3 Nucleus + 2.45 MeV Neutron
In Short:In Short: Fusion!Fusion!
Colleagues’ Reaction To the News:Colleagues’ Reaction To the News:
Shapira & Saltmarsh (2002) RepeatedShapira & Saltmarsh (2002) RepeatedTaleyarkhan ExperimentTaleyarkhan ExperimentResults:Results: at least three orders of magnitude at least three orders of magnitude fewerfewer
neutrons than the fusion of deuterium into neutrons than the fusion of deuterium into helium-3 should generate, even though their helium-3 should generate, even though their neutron detector is more efficient than neutron detector is more efficient than Taleyarkhan’sTaleyarkhan’s
Experimental Results not ReproducibleExperimental Results not Reproducible
In Short: Your Research . . .In Short: Your Research . . .
Taleyarkhan’s RebuttalTaleyarkhan’s Rebuttal Shapira & Saltmarsh “grossly overestimated detector Shapira & Saltmarsh “grossly overestimated detector
efficiency”efficiency” We have been able to reproduce the results, “many We have been able to reproduce the results, “many
times”times”
In Short,In Short,
Recent DevelopmentsRecent Developments Mild Support: (Flannigan & Suslick, 2005):Mild Support: (Flannigan & Suslick, 2005): Able to Obtain PlasmaAble to Obtain Plasma "A plasma is a prerequisite but certainly "A plasma is a prerequisite but certainly notnot a a
sufficient condition for fusion" sufficient condition for fusion" Maybe we could have fusion with molten salts or Maybe we could have fusion with molten salts or
liquid metals . . .liquid metals . . .
Sonoluminescence Remains a Phenomenon in Sonoluminescence Remains a Phenomenon in Search of an ExplanationSearch of an Explanation
??
References
Didenko, Y.T. & K.S. Suslick (2002). The Energy Efficiency of Formation of Photons, Radicals, and Ions During Single-Bubble Cavitation. Nature 418, 394-397
Glanz, J. (1996). The Spell of Sonoluminescence. Science 274, pp. 718-719Pool, R. (1994). Can Sound Drive Fusion in a Bubble? Science 266, p. 1804Putterman, S.J. (1995). Sonoluminescence - Sound into Light. Scientific American. 272, pp. 32-37Putterman, S.J. (1198). Star in a Jar. Physics World. 11, pp. 38-42Shapira, D., & M.J. Saltmarsh (2002). Comments on The Possible Observation of d-d Fusion in Sonoluminescence .
Physics Division, Oak Ridge National Laboratory.Taleyarkhan, R.P., C.D. West, J.S. Cho, R.T. Lahey Jr., R.I Nigmatulin, & R.C. Block (2002). Evidence for Nuclear
Emissions During Acoustic Cavitation. Science 295, pp. 1868-1873Taleyarkhan, R.P., R.C. Block, C.D. West, &, R.T. Lahey Jr., (2002). Comments on the Shapira & Saltmarsh Report.
Physics Division, Oak Ridge National Laboratory.