Cold Fusion at SRI An 18 Year Retrospective (and brief Prospective)

Transcription

1 Cold Fusion at SRI An 18 Year Retrospective (and brief Prospective) Michael McKubre Director of the Energy Research Center Principal Staff Scientist in the Materials Research Laboratory SRI International, Menlo Park, California. Presented at the APS meeting, Denver CO, March 5, 2007.

2 1989 A Series of Unanswered Questions Q1 Is there unexplained heat? Q2 Is the heat output sensibly correlated with inputs? Q3 Is the heat derived from a nuclear process? Q4 Nuclear ash correlated with the excess heat? Q5 Are their other nuclear effects? Q6 What is the nuclear process? Q7 What is the future?

3 1992 Q1 Unexplained heat source? YES!!! Effect Evidenced on numerous occasions (>70 at SRI) Typical P xs 3-30% (±0.5%) of Total P in (340%) Up to 90 observation of excess power effect Duration several hours to 1 week Sustained, unidirectional heat burst exhibit an integrated energy at least 100 times greater than conceivable energy storage effects Heat production observed for over half the operation time of one cell (C1). Similar heat production observed using 4 different calorimetric methods.

4 1995 Q2 Sensibly correlated with inputs? Necessary conditions: YES!!! Maintain High Average D/Pd Ratio (Loading ) For times >> x D/D (Initiation) At electrolytic i > mA cm -2 (Activation) With an imposed D Flux (Disequilibrium) Heat correlated with: - electrochemical current or current density - D/Pd loading - V ref. surface potential - Pd metallurgy - Laser stimulus For 1mm dia. Pd wire cathodes: P xs = M (x-x ) 2 (i-i ) i D x ~0.875, i =50-400mA cm - 2, id =1-10 ma cm - 2,t >200 D/D

5 Hermetic 10- pin Connector Gasket PTFE Top Plate Quartz Liner Electrolyte PTFE Liner Gas Tube Containing Catheter Screws Catalyst RTD Recombination Catalyst in Pt Wire Basket PTFE Spray Separator Cone PTFE Cap Pt Wire Anode SRI Quartz Calorimeter and Degree of Loading (DoL) Cell Pd Cathode Stainless Steel Outer Casing Quartz Anode Cage PTFE Base

6 Water In Acrylic Toppiece Gas Tube Exit to Gas-handling Manifold Inlet RTD's Water Out Hermetic 16-pin Connector Gasket Water Outlet Containing Venturi Mixing Tube and Outlet RTD's Acrylic Flow Separator SRI Labyrinth (L and M) Calorimeter and Cell Hermetic 10-pin Connector Stainless Steel Dewar Gasket PTFE Plate Catalyst RTD Screws Recombination Catalyst in Pt Wire Basket PTFE Spray Separator Cone Quartz Cell Body PTFE Liner PTFE Ring Pd Cathode Brass Heater Support and Fins Quartz Anode Cage Heater Pt Wire Anode Acrylic flow restrictor PTFE Ring Stainless Steel Outer Casing Locating Pin Stand

7 0.7 P13/14 Simultaneous Series Operation of Light & Heavy Water Cells; Excess Power & Current Density vs. Time I (A/cm^2) Pxs D2O (W) Pxs H2O (W) D 2 O

8 0.6 P13/14 Simultaneous Series Operation of Light & Heavy Water Cells; Excess Power vs. Current Density P14/D2O Linear P13/H2O I or i Electrochemical Current Density (A/cm 2 )

9 C1: Excess Power vs. D/Pd McKubre et al (similar to Kunimatsu et al) ICCF3, Nagoya. D/Pd 6 C1 Parabolic Atomic ratio (D/Pd)

10 Excess Power vs. Maximum Loading (1) 49 Experiments x Max R/R T1-2,OHF1-3 L1, 2, 7, (9, 6) 15 L12 P8 - P11 C1, P2, L3 AS2 AS1.1 C2, P14, P21 T3-4 P15 P4, L11 AS1.3 P12, 20 P3, P5, P6, L4, P16 Baranowski P19 P22 P Max. D/Pd~0.725 P1 1.1 (No heat, Heat) Figure 1 Maximum loading, D/Pd, attained in experiment; determined by R/R.

11 Excess Power vs. Maximum Loading (2) Heat Present Work SRI ENEA Heat previous work No Heat x Max Experiments More Maximumum loading [D/Pd].

12 Q3 Is the heat of nuclear origin? Yes! 100 s to 1000 s of ev s / Pd (D) atom SRI 2080 ev/pd, Energetics >4000 ev/pd Sustained, unidirectional heat burst exhibit an integrated energy at least 10 times greater than the sum of all possible chemical reactions within a closed cell Heat effects are observed with D, but not H, under similar (or more extreme) conditions McKubre et al, Development of Advanced Concepts, EPRI, TR (1994)

13 2000 Q4 Nuclear ash correlated with the excess heat? Q5 Uncorrelated nuclear products? Yes! Compelling Evidence: 4 He closely time and quantity correlated with excess heat 3 H observed in some cases only. Not quantity correlated with excess heat ( ~ 3-4 O.M. down) Isotopics effects possibly at very low level Charged particles:, p + possibly at even lower level Neutrons not observed at SRI (although I believe they can be found using more sensitive detectors at ~10 or more O.M. down from heat) Yes!

14 2000 Q4 Nuclear ash correlated with the excess heat? Q5 Uncorrelated nuclear products? Yes! Experiments: 2π, real time, in situ X-ray detector (Lockheed) Gamma and X-ray spectrometer (Wolf) Neutron spectrometer (Wolf & Lockheed) Charged particles:, p + (MIT) Residual isotopics effects (SRI & other) Tritium (SRI & Clarke) Helium: 3 He and 4 He (Amarillo, PNNL & Clarke) Results: Correlated heat and 4 He. Unequivocal evidence of Tritium production. Yes! McKubre et al, Emergence of a coherent explanation, Proc. ICCF8, Lerici (2000)

15 M4: Excess Energy - 4 He Correlation [Closed, He-leak tight, Mass-Flow Calorimeter, Accuracy ±0.35%] Measured Values Predicted Values Current Burst 1 P xs = M (x - x ) 2 (i - i ) Žx/Žt x =.833, i =.425, r= % Burst Time (hours) Electrochemical Current Density (A cm-2)

16 M4: Correlation of Heat with Helium 104±10% 10% 2.5 [4He] % of 24MeV 2.077± % 2 104±10% 100% ± ± % 62±5% 69±7% 60% 1 <-Extended period of thermal and compositional cycling-> 40% ± % 0 0% Time (hours)

17 To Mass Spectrometer Sample Volume Vacuum/Pressure Gauge To Digital Pressure Guage Pressure Transducer Extrel C-50 QMS Thermowell Containing Gas Phase and Solid Phase Thermocouple Sensors Sample Vacuum ppm Helium in Deuterium Calibration Mixtures 4% He 4% D 2 ln Ar Tune-up Mixture Carbon Trap (LN 2 cooled) Nupro 50cc 316SS Sample Flask Solid Insulation Helically Wound Heating Elements Nupro 50cc 316SS Sample Flask Case cell Studies: H 2 and D 2 Gas with Pd/C Catalyst Catalyst 1 Liter Stainless Steel Dewars Vessel 1 Vessel 2

18 Case: 4 He vs. time He in Room Air at STP SC1 SC2 SC3.1 SC3.2 SC4.1 SC Time (Days)

19 Case: Q -Value - Energy vs. 4 He 150 Gradient y = 18.36x R 2 = Differential y = 18.89x R 2 = 0.95 Gradient Q = 31±13 MeV/atom Differential Q = 32±13 MeV/atom Helium Increase (ppmv/v)

20 Production of Tritium in a Sealed Pd cavity e-beam Weld 0.3M LiOD AZ1 0.3M LiOD, AZ2 0.3M LiOH Cathodic Current 5-7.5A Current Density mA cm -2 P in W, Duration 120 Days P xs,max = 10 ±1.5%, P xs = 0 ±1.5%, Pd Bulk Pd Black D D2O Electrolysis OD- Deloaded: open circuit and at 2V Anodic for a further 100 Days. Arata/Zhang DS Cathode: 6cm long, 14mm dia., 3.5mm wall

21 AZ1&2 0.3M LiOH & LiOD with Arata/Zhang Double Structured Cathode Largest SRI Total P xs (and Tritium Generation) Effects of Light and Heavy water electrolysis Pxs H2O Pxs D2O fit %XS %XS Linear (Pxs H2O) Pxs/Pin and Uncertainty Max. = 9.9 ± 1.5% 12% 10% 8 8% Excess Power (W) 6 4 6% 4% y = x ±1.3W Input Power (W) 2% 0% -2%

22 AZ1: Radial Distribution of 3 He (and 3 H) 5 e-beam Weld 4 1 Arata/Zhang DS Cathode: 6cm long, 14mm dia., 3.5mm wall Electrolyte 0.3M LiOD D 2 O Section Pd Bulk D OD- 2 Pd Black He Million Atoms/mg Radial Position (cm)

23 Present Q6 What is the nuclear process? Primary product 4 He with ~24 MeV/ 4 He Relevant theory under construction: Hagelstein, Chubb 2, Preparata, etc.

24 Future Q7 What is next? Research consortia: e.g. SRI/MIT/NRL/ENEA/Energetics Technical development: > 10 x Heat Out / Power In Positive Temperature Coefficient? Time for Engineering?

25 Dardik - ENERGETICS Complex non-dc electrical perturbation results in: Increased Cathode absorption of H and D Enhanced Stimulation of Excess Heat Effects Glow Discharge Mass Flow Calorimeter: 600W/cm 3, P Out /P In > 3.7, E Out /E In > 6.7, >1000 ev/ Pd Atom. FP Electrolysis: P XS >1kW/cm 3, P Out /P In > 50, E Out /E In > 30, E XS > 1.1MJ ~3690 ev/ Pd Atom. DARPA - Energetics - SRI - ENEA - NRL - MIT Replication effort established August 2005.

26 Energetics - SuperWaves 6 One Two Three Four Sum

27 Dardik - ENERGETICS - Results: P XS Pin Pout COPE E Out = 1.14 MJ POut/PIn E Out / E In = E In = 40 kj Time (hours) 0