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

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Theme The controversy in Nanofluids over thermal conductivity and heat transfer coefficient is only one in science. Prominent scientists (Stokes, Rayleigh, Einstein, Hubble) have been involved over the past century Most of these controversies involve the nanoscale and find origin the interpretation thereof by classical physics instead of by quantum mechanics. The theme of this presentation illustrates such controversies. 1a

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

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Classical Heat Transfer Fourier Theory applicable to Macroscale Heat capacity of a substance is assumed an intensive 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 Richard Feynman 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 Nothing New! Paraphrasing Feynman 40 years later: 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 Classical v. QM Heat Capacity 5 Nanoscale kT eV Classical QM By QM, absorbed EM energy at the nanoscale cannot be conserved by an increase in temperature. How conserved?

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Conservation by QED 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. 6 For a spherical NP having diameter D, QED photons have f = QED photon frequency E = Planck energy c = light speed n r = refractive index h = Planck’s constant

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal 7  T = 0 Instead, Q QED is prompt non-thermal emission. In < 5 fs, before phonons move, conservation gives Q QED is not Stefan-Boltzmann – no high temperatures QED Induced Heat Transfer Replace Fourier Equation by: E = Photon Planck Energy dN/dt = Photon Rate 

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal QED Implications 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 not film vibrations Nanofluids Excluding QED emission leads to unphysical results 8

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Molecular Dynamics Akimov, et al. “Molecular Dynamics of Surface- Moving Thermally Driven Nanocars,” J. Chem. Theory Comput. 4, 652 (2008). Discrete  kT = 0, but kT > 0 assumed Car distorts but does not move Macroscopic analogy Instead, QM forbids any increase in car temperature. Hence, QED radiation is produced that by the photoelectric effect charges the cars that move by electrostatic interaction with each other. Sarkar et al., “Molecular dynamics simulation of effective thermal conductivity and study of enhance thermal transport in nanofluids,” J. Appl. Phys, 102, (2007). Periodic Boundary Conditions kT > 0, valid Metropolis & Teller, For discrete nanostructures, MD of heat transfer is not valid. MD and DFT of the bulk under periodic boundary conditions are valid.

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal 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 and redshift galaxy light without Doppler effect. 10

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal QED Induced Redshift 11

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Effect on Cosmology The redshift: Z = ( o - )/ > 0 occurs without the Universe expanding. Astronomers will not find the dark energy to explain an expanding Universe which is not expanding Higgs boson unlikely to be found at LHC because gravitational lensing measurement of dark matter is negated by cosmic dust Suggests a return to a static infinite Universe once proposed by Einstein. 12

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Prompted by classical heat transfer being unable to explain the reduced conductivity found in thin film experiments. Moreover, explanations of reduced conductivity based on revisions to Fourier theory by phonons are difficult to understand and concluded by hand-waving 13 * T. Prevenslik, “Heat Transfer in Thin Films,” Third Int. Conf. on Quantum, Nano and Micro Technologies, ICQNM 2009, February 1-6, Cancun, Proceedings of MNHMT09 Micro/Nanoscale Heat and Mass Transfer International Conference, December 18-21, 2009, Shanghai. Thin Films*

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Reduced Conductivity 14 QED Heat Transfer Q Cond = Q Joule - Q QED ~ 0 K eff  T = (Q Joule - Q QED ) (d f + d S ) / A  T small, K eff ~ Bulk No Reduced Conductivity Q QED Q Cond TT Current Approach Q Cond = Q Joule K eff  T = Q cond (d f + d S )/A  T large, K eff small Reduced Conductivity Q Joule Film Substrate dfdf dSdS KfKf KSKS

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

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal 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 16 * T. Prevenslik, “Thermophones by Quantum Mechanics,” ITHERM 2010, June 2-5, Las Vegas, 2010 Thermophones*

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Classical Theory of Sound Classical physics requires air vibration by diaphragm – wires? Thin film (wires) theory by Arnold & Crandall in

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal QM Theory of Sound In 2008, Xiao et al. showed sound produced in CNT film, but no vibration measured means classical theory not applicable. Can sound be produced without film vibration? 18

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Nanofluids* * T. Prevenslik, “Nanofluids by QED Induced Heat Transfer,” IASME/WSEAS 6th Int. Conf. Heat Transfer, HTE-08, August, Rhodes, 2008, “Nanofluids by Quantum Mechanics,” Micro/Nanoscale Heat and Mass Transfer International Conference, December 18-21, Shanghai, Prompted by classical theory being unable to explain how NPs increase thermal conductivity of common solvents Moreover, tests showed enhancements in conductivity far greater than given by standard mixing rules. Heat Transfer (not Conductivity) enhanced 19

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Heat Transfer Enhancement Heat by collisions into NP in the FIR (10 micron penetration) NPs avoid Local Thermal Equilibrium 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 20

DNA Damage by NPs 20a ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Experiments show NPs cause DNA damage mimics that by conventional ionizing radiation

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal * T. Prevenslik, “Boiling of nanofluids at a surface by quantum mechanics,” at “Boiling Heat Transfer, 2010” Pool Boiling* 21 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

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal 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, Application* 22

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal PC Cooling* * Schroeder,et al., “Nanofluids in a Forced-Convection Liquid Cooling System – Benefits and Design Challenges,“ ITHERM 2010, June 2-5, Las Vegas, Bellerova et al., “Spray Cooling by Al2O3 and TiO2 Nanoparticles in Water,” ITHERM 2010, June 2-5, Las Vegas, Surprisingly, both papers strongly rebuked the long history of nanofluids as enhanced coolants Reports of small increases in HTC in channels and HTC decreases in spray cooling compared to water alone but both papers neglected QED radiation losses HTC = heat transfer coefficient 23

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal PC Cooling 24 Correct Literature for QED radiation losses not included in temperature changes of nanofluid

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal 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 extensive property depending on size and amount of substance MD heat transfer simulations of discrete nanostructures are invalid, but DFT of the bulk and dynamics of discrete QED charged nanostructures are 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 – go from there. 25

ECI - NANOFLUIDS: Fundamentals and Applications II, August 15-20, 2010, Montreal Questions & Papers