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QED Induced Heat Transfer

QED Induced Heat Transfer. Thomas Prevenslik QED Radiations Discovery Bay, Hong Kong. 1. Introduction. In 1822, Fourier published the transient heat conduction equation. where, c is the specific heat based on the concept of Lavoisier and Laplace in 1783. 2. Classical Heat Transfer.

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QED Induced Heat Transfer

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  1. QED Induced Heat Transfer Thomas Prevenslik QED Radiations Discovery Bay, Hong Kong 1 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  2. Introduction In 1822, Fourier published the transient heat conduction equation where, c is the specific heat based on the concept of Lavoisier and Laplace in 1783 2 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  3. Classical Heat Transfer Fourier Theory applicable to Macroscale Heat capacity c of a substance is assumed an extensive property independent of quantity of substance or size, but at nanoscale has a problem with quantum mechanics - QM Propose QED induced radiation as the heat transfer mechanism at the nanoscale QED = quantum electrodynamics 3 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  4. Richard Feynman -1970 Classical physics by statistical mechanics allows the atom to have heat capacity at the nanoscale. QM also allows atoms to have heat capacity at the nanoscale, but only at high temperature. Submicron wavelengths that fit into nanostructures have heat capacity only at temperatures > 6000 K At 300 K, heat capacity is therefore “frozen out” at submicron wavelengths QM does not allow nanostructures at ambient temperature to conserve absorbed EM energy by an increase in temperature 4 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  5. Classical v. QM Heat Capacity Classical kT 0.0258 eV QM Nanoscale By QM, absorbed EM energy at the nanoscale cannot be conserved by an increase in temperature 5 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  6. f = QED photon frequency E = Planck energy c = light speed nr = refractive index h = Planck’s constant Conservation of EM Energy Recall from QM, QED photons of wavelength  are created by supplying EM energy to a box having sides separated by  / 2. Absorbed EM energy is conserved by creating QED photons inside the nanostructure - by frequency up - conversion to the resonance of the nanostructure. For a spherical NP having diameter D, QED photons have 6 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  7. QED Heat Transfer Instead, QQED is prompt non-thermal emission Replace Fourier Equation by: E= Photon Planck Energy dN/dt = Photon Rate QQED is not Stefan-Boltzmann T = 0 7 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  8. QED Emission in NPs Thin Films Joule Heat QED Emission  = 2Dnr Astronomy Galaxy Light DNA Damage Collisions Residual kT Energy Tribochemistry NP Specific Heat Vanishes No Temperature change 8 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  9. QED Applications Molecular Dynamics Heat transfer simulations invalid for discrete nanostructures Big Bang Theory QED Redshift in cosmic dust means Universe is not expanding Thin Films QED emission negates reduced conductivity by phonons Thermophones Sound by QED emission Nanofluids Excluding QED emission leads to unphysical results 9 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  10. Akimov, et al. “Molecular Dynamics of Surface-Moving Thermally Driven Nanocars,” J. Chem. Theory Comput. 4, 652 (2008). Discrete, No Periodic Boundary Conditions kT = 0, but kT > 0 assumed Car distorts and buckles, but does not move Instead, nanocar charged by QED radiation Charged cars move by electrostatics Sarkar et al., “Molecular dynamics simulation of effective thermal conductivity and study of enhance thermal transport in nanofluids,” J. Appl. Phys, 102, 074302 (2007). Periodic Boundary Conditions kT > 0 Molecular Dynamics MD of heat transfer not valid for discrete nanostructures 10 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  11. Big Bang Theory In 1929, Hubble measured the redshift of galaxy light that based on the Doppler Effect showed the Universe is expanding. However, cosmic dust which is submicron NPs permeate space redshift galaxy light without Doppler effect. 11 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  12. QED Induced Redshift 12 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  13. Conclusions The redshift: Z = (o - )/ occurs without the Universe expanding. Astronomers will not find the dark energy to explain a Universe which is not expanding Suggests a return to a static Universe once proposed by Einstein. 13 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  14. Thin Films* * T. Prevenslik, “Heat Transfer in Thin Films,” Third Int. Conf. on Quantum, Nano and Micro Technologies, ICQNM 2009, February 1-6, Cancun, 2009. Proceedings of MNHMT09 Micro/Nanoscale Heat and Mass Transfer International Conference, December 18-21, 2009, Shanghai. Prompted by classical heat transfer unable to explain the reduced conductivity found in thin film experiments. Moreover, explanations of reduced conductivity based on revisions to Fourier theory by phonons as quanta in the BTE are difficult to understand and concluded by hand-waving 14 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  15. QQED QED Heat TransferQCond = QJoule - QQED ~ 0 KeffT = (QJoule- QQED) (df + dS ) / A T small, Keff ~ Bulk No Reduced Conductivity Reduced Conductivity QJoule Substrate Current ApproachQCond = QJoule KeffT= Qcond (df + dS )/A T large, Keff small Reduced Conductivity T KS Film Kf dS QCond df 15 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  16. QED Emission QED emission negates reduced conductivity 16 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  17. Thermophones* * T. Prevenslik, “Thermophones by Quantum Mechanics,” ITHERM 2010, June 2-5, Las Vegas, 2010 Over a century ago, Stokes communicated to the Royal Society in 1880 the finding by Preece that electrical wires produced sound. In 1914, Rayleigh reported de Lange’s thermophone using wires to the Royal Society 17 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  18. Classical Theory of Sound Thin film (wires) theory by Arnold & Crandall in 1917. Classical heat transfer was used to determine the temperatures that cause pressure changes that produce sound from vibration of air molecules 18 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  19. QM Theory of Sound In 2008, Xiao et al. showed sound produced in CNT film, but no vibration means classical theory not applicable. Can sound be produced without vibration? 19 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  20. Nanofluids* Prompted by classical theory unable to explain how NPs increase the thermal conductivity of common solvents Transient Hot Wire tests show enhancements far greater than given by Hamilton & Crosser (HC) mixing rules. *T. Prevenslik, “Nanofluids by QED Induced Heat Transfer,” IASME/WSEAS 6th Int. Conf. Heat Transfer, HTE-08, 20-22 August, Rhodes, 2008, “Nanofluids by Quantum Mechanics,” Micro/Nanoscale Heat and Mass Transfer International Conference, December 18-21, Shanghai, 2009. 20 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  21. keff = Effective kf = Fluid kP = NP  = Volume fraction HC Mixing Rules HC extended Maxwell’s rules for electrical to thermal conductivity of macroscopic particles. Applicable to nanoparticles. HC mixing rules valid for thermal conductivity 21 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  22. QM Enhancement Heat into NP in the FIR (10 micron penetration) LTE avoided Heat out of NP beyond the UV (1-10 centimeter penetration) Penetration Ratio R = UV / FIR R > 1 Heat is transferred over greater distance with NPs than without NPs  enhancement 22 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  23. Nanofluids by QM Heat Transfer enhanced – not thermal conductivity 23 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  24. Pool Boiling* * T. Prevenslik, “Boiling of nanofluids at a surface by quantum mechanics,” www.nanoqed.org at “Boiling Heat Transfer, 2010” Paradox : High CHF without increased BHT coefficient CHF – critical heat flux BHT – boiling heat transfer Explained by QED radiation from NPs bypassing boiling surface and dissipating heat in the bulk 24 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  25. Application* Too complex for analysis Experiment using UV fluorescence with chemical markers * You, et al., “Effect of nanoparticles on critical heat flux of water in pool boiling heat transfer,” Appl. Phys Lett., 83, 3374, 2003. 25 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  26. PC Cooling* Papers strongly questioned nanofluids as a coolant Reports of small increases in HTC in channels and HTC decreases in spray cooling compared to water alone but neglected QED radiation losses HTC = heat transfer coefficient * Schroeder,et al., “Nanofluids in a Forced-Convection Liquid Cooling System – Benefits and Design Challenges,“ ITHERM 2010, June 2-5, Las Vegas, 2010. Bellerova et al., “Spray Cooling by Al2O3 and TiO2 Nanoparticles in Water,” ITHERM 2010, June 2-5, Las Vegas, 2010. 26 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  27. PC Cooling Correct Literature for QED radiation losses not included in temperature changes of nanofluid 27 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  28. Conclusions Classical heat transfer based on statistical mechanics at the nanoscale is negated by QM because the heat capacity of the atom vanishes QED heat transfer conserves absorbed EM energy by prompt non-thermal QED radiation negates conductive heat flow by phonons Phonon derivations of reduced thermal conductivity are meaningless because conduction does not occur. Heat capacity is an intensive and not an extensive property MD heat transfer simulations of discrete nanostructures are invalid, but DFT and dynamics of QED charged nanostructures is valid. Transient Fourier heat flow may be replaced by the a priori assumption that absorbed EM energy is emitted by QED at the frequencies of the EM resonances of the nanostructure. 28 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

  29. Questions & Papers Email: nanoqed@gmail.com http://www.nanoqed.org 29 ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal

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