NANO-DEVICES FOR ENHANCED THERMAL ENERGY STORAGE, COOLING AND SENSING

Transcription

1 NANO-DEVICES FOR ENHANCED THERMAL ENERGY STORAGE, COOLING AND SENSING Debjyoti Banerjee, Ph.D. Faculty Fellow, 3M Corp. ( ) Faculty Fellow, Mary Kay O Connor Process Safety Center Morris Foster Faculty Fellow ( 07-09) & Associate Professor of Mechanical Engineering Summer Faculty Fellow (ASEE) Air Force Research Lab. (AFRL) 06, 07 SPAWAR 09 Dwight Look College of Engineering Texas A&M University College Station, TX March 19, of 104

2 Contents Dip Pen Nanolithography (DPN) Cooling & Thermal Storage (Solar Thermal Energy) CNT and Silicon Nanofins Nano-Fluids Molecular Dynamics (MD) Simulations Acknowledgements 2 of 104

3 Multiphase Flows & Heat Transfer Lab. (Since Jan. 2005, 36 Extra-Mural Funded Projects) Nano-Sensors (2 Ph.D., 1 M.S.) MEMS: TEES: Nano-calorimeter (EXPLOSIVES SENSOR) Nano-MEMS Research/NSF SBIR: RF-MEMS,RF-Tuner DPN (Dip Pen Nanolithography): DARPA/MTO: chirality control, low temp. synthesis of CNT ONR STTR/ ADA Tech.: Ultra-Capacitors SPAWAR: low temp. synthesis of Graphene (ONR/ASEE) TSGC: Nanolithography+Microfluidics, CFD GE Research: Silicon Nanofins Bio-Microfluidics, Lab-On-Chip: AFRL: Portable water quality monitor DARPA/MF 3 : Micro-Chamber Filling» (1) Vaccine Storage/ Paper microfluidics,» (2) Anthrax Detection using CD Microfluidics NASA: Lipid bi-layer sensors for studying protein/peptide kinetics AFOSR: Reconfigurable microfluidic device for nano-optics (META MATERIALS) Thermal Management (3 Ph.D., 1 M.S.) Nanostructures ONR: Flow Boiling on Carbon Nanotubes NSF: Pool Boiling on Silicon Nanofins, Molecular Dynamics DOE: Nanofluids for Thermal Energy Storage (SOLAR ENERGY) AFOSR/AFRL(ASEE-SFFP): Nano-Fluids Qatar National Research Foundation (QNRF): Nanofluids and Nanofins for enhanced heat transfer Photronics Corp./ Trianja Tech. (Si Values Partners/ B G Group): Nanofluids for energy app. Irvine Sensors: Micropump Design for Electronics Cooling (AFRL SBIR Phase II) Aspen Thermal Systems: Compact condensers (ONR SBIR Phase I; Phase II) Biomedical Device (Surgical Sterilizer) Lynntech/ ARO SBIR Phase II: Portable sterilizer for surgical tools using steam. 3 of 104

4 Nano-Fluids/ Nano-Coating Research Demonstrated 40% enhancement in performance of compact heat exchangers using carbon nanotube (CNT) based nano-fluids in Poly Alpha Olefin (PAO) oils (sponsored by Air Force Research Lab.) Specific Heat enhanced by ~20% Viscosity enhanced by 12.5% Demonstrated 10% enhancement in convective heat transfer in flow loop cooling using exfoliated graphite nanoparticles in Poly-Alpha-Olefin (PAO) Coolants/ Nanofluids (sponsored by Air Force Research Lab.) Specific Heat enhanced by ~50% Viscosity enhanced by 10X Demonstrated ~20-120% enhancement in specific heat capacity of high temperature nanofluids (molten salt eutectics and solar salts) for applications in Concentrated Solar Power (CSP) Thermal Energy Storage (TES). (sponsored by the Department of Energy/ DOE Solar Energy Technology Program/ SETP). Demonstrated ~ % enhancement in pool boiling using carbon nanotube (CNT) coatings (sponsored by Office of Naval Research, National Science Foundation) Demonstrated ~120% enhancement in Critical Heat Flux (CHF) for pool boiling on silicon nano-fins (sponsored by National Science Foundation) Demonstrated ~180 % enhancement in flow boiling using carbon nanotube coatings (sponsored by Office of Naval Research) Demonstrated 100% enhancement in performance of Compact Condensers using carbon nanotube (CNT) coatings (collaboration with Aspen Thermal Systems; Sponsor: Office of Naval Research/ ONR Thermal Management Program). Leakage issues. ~ % enhancement in spray cooling (with phase change) using Titania nano-coatings. 4 of 104

5 CNT Synthesis at ~ C!! Gargate and Banerjee (Scanning, 2008) Synthesis on heated AFM Tip (TAMU) 5 of 104

6 Multi-Phase Flows Research Current Research Focus: NANO-FINS for Thermal Management Nanofluids Micro/Nano-thermocouples (Thin Film Thermocouples or TFT ) Carbon Nanotubes (CNT) Molecular Dynamics simulation Boiling Chaos WHY NANO? TOP VIEW SECTION VIEW 6 of 104

7 Heat Flux (W/cm 2 ) Cooling improved by 30%-300% using Nanotubes Critical Heat Flux improves by 60% POOL BOILING OF PF-5060 (3M Corp.) Type A: 10 mm Type B: 25 mm Banerjee, et al. J. of Heat Transfer, 2006 Saturation case with Bare silicon wafer Run-2 Wall Superheat ( C) 5-Degree Subcooling with Bare Silicon Wafer 10- Degree Subcooling With Bare Silicon Wafer Run-2 Saturation Case With Type-A CNT 5-Degree Subcooling with Type-A CNT Saturation Case type-b CNT 5-Degree Subcooling with type-b CNT Run-2 10-Degree Subcooling with type-a CNT Run-2 5-Degree Subcooling with type-b CNT Run-1 10-Degree Subcooling with type-b CNT Run-2 (Ahn, et al., JHT 2006, 2009; AIAA 2007) 7 of 104

8 Heat flux (W/cm 2 ) Silicon Nano-Fins Critical Heat Flux improves by 120% Nucleate Boiling Curve for q n " (W/cm 2 ) DT Sub = 0 o C Wall Superheat ( o C) 100 nm Run1 100 nm Run2 336 nm Run1 336 nm Run2 259 nm Run1 259 nm Run2 Bare Sriraman and Banerjee, ASME- IMECE 2007, of 104

9 Nano-Fin The Nano-Fin Effect R 1 Resistance due to finite thermal conductivity of Silicon Substrate R 2 Resistance at the Substrate -Nano-Fin interface R 3 Resistance due to finite thermal conductivity of Nano-Fin R 4 Interfacial Thermal Resistance between Nano- Fin and surrounding Fluid. Nano-Fin R 3 R 2 R 1 Resistance (m 2 K/W) (A) Son et al, J of Applied Physics, 2006; (B) Murad et al, Chemical Physics Letters, 2009; (C) Huxtabale et al, Nature, 2003, R 4 Silicon Nano-Fin Heater Substrate Carbon Nanotube R R 2 - ~ (A) R 3 Very Low Very Low R 4 ~ [B] ~ 10-8 [C] Fluid Molecules 9 of 104

10 Ln(dT) (K) Ln(dT) (K) Effect of Nano-Fins and Nano-Fluids (CuO Nano-Particles in Water) Nanofluids with Carbon Nanotube Coatings Carbon Nanotubes as nano-fins enhance heat transfer Modeling of thermal interface resistance (Kapitza resistance) Nanofins 7 SWNT (5,5) K 750k k Linear (500K) 1 Linear (750k) Linear (1000k) Time (ps) Thermal interface resistance (R k ) : R C k A T Unnikrishnan, Reddy, Banerjee ; Int. J. Thermal Sciences (2008) T Nanofluids SWNT (5,5) Water & CuO Time (ps) 500K 750k 1000k Linear (500K) 10 of 104

11 Equilibrium Molecular Structure Equilibrium structure snapshot for n-tridecane (Scale is in Å) Radial Distribution of Density Singh, N., 2010, PhD Thesis, Texas A&M 11 of 104

12 Nanofluid RESULTS Specific heat enhanced by % by CNT 0.1% by weight Specific heat enhanced by % by silica 1-2% Specific heat enhanced by 15 % by silica 1% Specific heat enhanced by 20 % by silica 1% Specific heat enhanced by 5% by silica (Therminol 1% Synthesis conditions affect properties of nanofluids! Publications: 23 peer-reviewed conference papers published 3 PHD Thesis D. Shin (2011): Assistant Professor, University of Texas at Arlington S. Jung (2012): Samsung B. Jo (2012): Post Doc., Texas A&M 5 journal papers published or accepted AIAA J. Thermophysics & Ht. Tr. (2009), ASME Journal Heat Transfer (2011, 2012), International Journal of Heat and Mass Transfer (2011), International Journal of Structural Change in Solids (2011) 12 of 104

13 Nanofluids in Microchannel Experimental setup for temperature measurement using TFT (nano-sensor array) Heater Inlet Outlet Average height of nanofins : nm Average diameter of nanofins : nm 13 of 104

14 Nanofluids in Microchannel Control experiment repeated after nanofluids experiments Shows same level of enhancement as the nanofluids experiments! Thermophysical properties of a working fluid are NOT the primary driver for the enhancement of heat transfer in the nanofluids experiments! Engineered nanofins show same level of enhancement as nanofluid experiments (or the control experiments repeated after nanofluids experiments) Transport mechanism Precipitation of nanoparticles Isolated precipitation Excessive precipitation Nanofin Fouling or scaling 14 of 104

15 Diode Temperature Nano-Sensor Array (DTSA) Sensing Principle : Diode Equation I exp qv I 1 0 nkt Barth & Angel Model N*(N-1) diodes N wires Current Study Model N*N diodes 2*N wires 15 of 104

16 Spray Cooling on Titania Nanocoatings Experimental Set-up At AFRL Scott Hansen, MS Thesis, Texas A&M University, of 104

17 Frames from Hi-Speed Movie Scott Hansen, MS Thesis, Texas A&M University, of 104

18 Pool Boiling Chaos: Experimental Apparatus Top Left: Schematic of Thin Film Thermocouple (TFT). Top Right: Packaged TFT. Above: Schematic of experimental Setup Right: Schematic Depicting the installed test surface Sathyamurthi and Banerjee, 2010, Int. Heat Tr. Conf. (IHTC2010) Sathyamurthy, V., 2009, PHD Thesis, Texas A&M 18 of 104

19 Summary & Conclusion Nano-Fin Effect cause heat transfer enhancement on nano-structures during Boiling: enhanced liquid-solid interactions, disruptions Nano-Fluids: nano-particles precipitate to form nano-fins. MD Simulations show that chemical properties affect heat transfer on nano-fins. Nanoparticle precipitation controls heat transfer in nanofluids Partial precipitation causes enhancement of heat flux Excessive precipitation causes degradation of heat flux 19 of 104

20 Summary & Conclusion Kapitza Resistance (ITR) is affected by the chemical composition (and chemical structure) of the solvents. Interaction potential between the nanotubes and solvent atoms is critical. Affected by length of polymer chains (polymerization), isomers & mixtures. Ability of the polymer chains to wrap around the nanotube. Density oscillations (compressed phase) of solvent molecules on nanoparticle surface can also affect thermal properties. Acts as a thermal capacitor (energy storage) Applications in solar thermal energy. In spray cooling local heat flux enhanced by ~ 8 times. Temperature gradients can be ~ 10 3 C/m. Temperature transients can reach ~10 3 C/s. 20 of 104

21 Contact Information Debjyoti ( DJ, Deb ) Banerjee 3123 TAMU, Texas A&M Mechanical Engineering College Station TX Ph: (979) Fax: (979) dbanerjee@tamu.edu Thermal Technologies Emerging Technologies Micro- Cantilever Sensor 21 of 104