D Banerjee Abstract 2009c

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Research: http://www1.mengr.tamu.edu/mpf/ Page 1 of 6 Ph: (979) 845-4500, Fax: (979) 845-3081 Email: [email protected] 03/13/2009 NANO-DEVICES FOR ENHANCED COOLING, STORAGE AND SENSING Debjyoti Banerjee, Ph.D. Morris Foster Faculty Fellow (2007-2009) and Assistant Professor of Mechanical Engineering; Faculty Fellow, Mary Kay O'Connor Process Safety Center; ASEE Faculty Fellow, SPAWAR/ Office of Naval Research (ONR) 2009 Mail Stop 3123, Texas A&M University, College Station, TX 77843-3123. Ph: (979) 845-4500, Fax: (979) 845-3081 Email: [email protected] ABSTRACT: Our research combines: (a) cooling and thermal storage technologies with (b) nano-technology. In the thermal area – we are investigating micro-scale heat transfer phenomena in boiling. Micron-scale features in boiling cause the formation of “cold spots”. These cold-spots are able to transmit almost 60-90% of the total heat transfer. Using Carbon Nano-Tube coated surfaces cooling was enhanced by 30-300%, probably due to enhancement of these cold spots in boiling. Using silicon nano-fins - cooling was enhanced by 120%. The applications are in materials processing and thermal management (cooling). We have also demonstrated cooling enhancement by ~8-30% using nanofluids. We are currently exploring the use of nanofluids for solar thermal energy conversion. DPN™ (Dip Pen Nanolithography) is a versatile technology that leverages microfluidic ink delivery systems with Scanning Probe Microscopy. In earlier studies the DPN process was enhanced through the development of commercial microfluidic devices called “Inkwells™”. We are currently developing the next generation microfluidic devices for DPN (e.g., Fountain Pen Nanolithography). The applications are in nano-catalysis, combinatorial nano-synthesis, bio-nanotechnology (e.g., cancer nanotechnology), maskless-lithography and nano-sensors for homeland security, bio-security and explosives detection (e.g., “nano-nose” and “nano-tongue”). We have invented a process for synthesizing Carbon Nanotubes of a single chirality (either metallic or semi-conducting) using DPN. Biography: Prior to Texas A&M University, Dr. Banerjee worked as a Manager of Advanced Research & Technology (ART) group at Applied Biosystems Inc. ($2B annual revenue), CA, where he managed a group of 10 engineers and scientists (6 Ph.D.). Previously in a singular capacity, Dr. Banerjee developed from concept to a commercial product at NanoInk Inc. (called “InkWells™). Inkwells are microfluidic platforms used for bio/nano-technology applications. Dr. Banerjee has 2 issued patents, submitted 4 provisional patent applications, while working at ABI, Ciphergen Biosystems, NanoInk and Coventor Inc. Dr. Banerjee received his Ph.D. in Mechanical Engineering from UCLA (with minor in MEMS) and received the “2001 Best Journal Paper Award ” from the ASME Heat Transfer Division (HTD). He received 3 M.S. degrees and was invited to 4 national honor societies. He attended the Indian Institute of Technology (IIT), Kharagpur for his Bachelor of Technology (Honors). At the graduation convocation at IIT he received the “Amlan Sen Best Mechanical Engineering Student Award (Endowment) ”. He also received the “Jagdish Bose National Science Talent Scholar” award from the Government of India. Dr. Banerjee received the “New Investigator Award (2005)” from the Texas Space Grants Consortium (TSGC), the “ASEE/AFOSR Summer Faculty Fellowship (2006, 2007)” at AFRL, the “ASEE/ONR Summer Faculty Felloship” at SPAWAR, “Morris Foster Fellowship (2007-2008)” from Mechanical Engineering Department at Texas A&M University and was designated as a Faculty Fellow at the Mary Kay O’Connor Process Safety Center at the Texas A&M University. He received the “3M Corporation Non-Tenured Faculty Fellowship (2009-2012). Dr. Banerjee’s research interests are in thermo-fluidics (boiling, nanofluids), solar thermal energy, MEMS/ microfluidics and nanotechnology (DPN, nano-synthesis and bulk synthesis of CNT and graphenes). Research Sponsors/ Collaborators: NSF, DARPA, SPAWAR, US Air Force (AFRL, AFOSR), Navy (ONR), Army (ARO), Texas Space Grants Consortium (TSGC), NASA (URETI/TiiMS), Nano-MEMS Research, DOE, Qatar National Research Foundation (QNRF), Lynntech, Aspen Thermal System, Irvine Sensors, Anteon Corp (General Dynamics), General Electric – Corporate Research & Development (GE-CRD), 3M Corp.

Transcript of D Banerjee Abstract 2009c

Page 1: D Banerjee Abstract  2009c

Research: http://www1.mengr.tamu.edu/mpf/

Page 1 of 6 Ph: (979) 845-4500, Fax: (979) 845-3081 Email: [email protected] 03/13/2009

NANO-DEVICES FOR ENHANCED COOLING, STORAGE AND SENSING

Debjyoti Banerjee, Ph.D. Morris Foster Faculty Fellow (2007-2009) and Assistant Professor of Mechanical Engineering;

Faculty Fellow, Mary Kay O'Connor Process Safety Center; ASEE Faculty Fellow, SPAWAR/ Office of Naval Research (ONR) 2009

Mail Stop 3123, Texas A&M University, College Station, TX 77843-3123. Ph: (979) 845-4500, Fax: (979) 845-3081 Email: [email protected]

ABSTRACT: Our research combines: (a) cooling and thermal storage technologies with (b) nano-technology. In the thermal area – we are investigating micro-scale heat transfer phenomena in boiling.

Micron-scale features in boiling cause the formation of “cold spots”. These cold-spots are able to transmit almost 60-90% of the total heat transfer. Using Carbon Nano-Tube coated surfaces cooling was enhanced by 30-300%, probably due to enhancement of these cold spots in boiling. Using silicon nano-fins - cooling was enhanced by 120%. The applications are in materials processing and thermal management (cooling). We have also demonstrated cooling enhancement by ~8-30% using nanofluids. We are currently exploring the use of nanofluids for solar thermal energy conversion.

DPN™ (Dip Pen Nanolithography) is a versatile technology that leverages microfluidic ink delivery systems with Scanning Probe Microscopy. In earlier studies the DPN process was enhanced through the development of commercial microfluidic devices called “Inkwells™”. We are currently developing the next generation microfluidic devices for DPN (e.g., Fountain Pen Nanolithography). The applications are in nano-catalysis, combinatorial nano-synthesis, bio-nanotechnology (e.g., cancer nanotechnology), maskless-lithography and nano-sensors for homeland security, bio-security and explosives detection (e.g., “nano-nose” and “nano-tongue”). We have invented a process for synthesizing Carbon Nanotubes of a single chirality (either metallic or semi-conducting) using DPN. Biography: Prior to Texas A&M University, Dr. Banerjee worked as a Manager of Advanced Research &

Technology (ART) group at Applied Biosystems Inc. ($2B annual revenue), CA, where he managed a group of 10 engineers and scientists (6 Ph.D.). Previously in a singular capacity, Dr. Banerjee developed from concept to a commercial product at NanoInk Inc. (called “InkWells™). Inkwells are microfluidic platforms used for bio/nano-technology applications. Dr. Banerjee has 2 issued patents, submitted 4 provisional patent applications, while working at ABI, Ciphergen Biosystems, NanoInk and Coventor Inc. Dr. Banerjee received his Ph.D. in Mechanical Engineering from UCLA (with minor in MEMS) and received the “2001 Best Journal Paper Award” from the ASME Heat Transfer Division (HTD). He received 3 M.S.

degrees and was invited to 4 national honor societies. He attended the Indian Institute of Technology (IIT), Kharagpur for his Bachelor of Technology (Honors). At the graduation convocation at IIT he received the “Amlan Sen Best Mechanical Engineering Student Award (Endowment)”. He also received the “Jagdish Bose National Science Talent Scholar” award from the Government of India. Dr. Banerjee received the “New Investigator Award (2005)” from the Texas Space Grants Consortium (TSGC), the “ASEE/AFOSR Summer Faculty Fellowship (2006, 2007)” at AFRL, the “ASEE/ONR Summer Faculty Felloship” at SPAWAR, “Morris Foster Fellowship (2007-2008)” from Mechanical Engineering Department at Texas A&M University and was designated as a Faculty Fellow at the Mary Kay O’Connor Process Safety Center at the Texas A&M University. He received the “3M Corporation Non-Tenured Faculty Fellowship (2009-2012). Dr. Banerjee’s research interests are in thermo-fluidics (boiling, nanofluids), solar thermal energy, MEMS/ microfluidics and nanotechnology (DPN, nano-synthesis and bulk synthesis of CNT and graphenes). Research Sponsors/ Collaborators: NSF, DARPA, SPAWAR, US Air Force (AFRL, AFOSR), Navy (ONR), Army (ARO), Texas Space Grants Consortium (TSGC), NASA (URETI/TiiMS), Nano-MEMS Research, DOE, Qatar National Research Foundation (QNRF), Lynntech, Aspen Thermal System, Irvine Sensors, Anteon Corp (General Dynamics), General Electric – Corporate Research & Development (GE-CRD), 3M Corp.

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BOILING ON NANO-STRUCTURED SURFACES

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 Bare Silicon Saturation Bare Silicon 5 ºC Subcooled

Type‐A Saturation Type‐A 5 ºC Subcooled

Type‐B Saturation Type‐B 5 ºC Subcooled

Figure 1. Boiling on Carbon Nanotube (CNT) coated silicon wafer for PF5060 refrigerant. The results show a 30-300% enhancement in heat transfer. Experiments were performed in the research group of PI. (ASME J. Heat Transfer, 2006; 2008).

Figure 2. Boiling on Silicon Nanofins. Pool boiling heat flux was enhanced by ~120% on heaters with silicon nano-fins (SEM of nanofins shown in inset). Silicon nano-fin geometry: ~100 nm height, ~200 nm diameter, .~800 nm pitch (ASME-IMECE 2007).

Nucleate Boiling Curve for qn" (W/cm2)

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30 - 300% Enhancement in Cooling

Height of CNT Type A: 9 microns Type B: 25 microns

120% Enhancement in Cooling

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TEMPERATURE MICRO/NANO-SENSORS FOR BOILING MEASUREMENTS

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(a) (b) (c) Figure 3. SEM images of (a, b) Thin Film Thermocouples (TFT), integrated with (c) Carbon Nanotubes (CNT): The CNT structures are 9-25 microns in height and 8-16 nm diameters. The integrated device was used to study transport mechanisms in pool boiling. Heat transfer enhancement of ~30-300% was achieved. (J. Heat Transfer, ’06)

Bond Pads

Thermocouple Junction

Bond Pads

Chromel Alumel Figure 4. Temperature Micro-sensors: Thin Film Thermocouples (TFT) (a) Mask Layout, and (b) Fabrication (using photolithography, physical vapor deposition, and lift-off process) on silicon and pyrex wafers. K-Type was chosen for their sensitivity and broad linearity. The Chromel and Alumel layers are ~200nm thick, ~ 30microns wide and the junctions are on 200 microns pitch. (J. Components & Packaging Tech., ‘06)

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Figure 5. Cold Spot: (a) Simulation results showing “cold spot” dynamics in boiling of water on a steel heater. This received the “Best Journal Paper Award” from the ASME Heat Transfer Division. The animation movies can be downloaded from PI’s research website. Wire frame depicts vapor bubble. Heat Flux = 1.68 W/cm2. (Banerjee and Dhir, ASME-IMECE ’96; J. Heat Tr. ’02). Color Code: Red: High, Blue: Low temperature. (b) Fast Fourier Transform (FFT) of temperature fluctuations recorded from pool boiling experiments using surface micro-machined temperature micro-sensors (thin film thermocouples). The FFT data shows frequency peaks in temperature in the 10-15 Hz range – showing the existence of “cold spots”. (AIAA Paper No. 06-5586).

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COLD SPOT

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NANOFLUIDS FOR ENHACNED COOLING & MOLECULAR DYNAMICS

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(a) (b) Figure 6. Nanofluids in Fin Cooler (a) Experimental apparatus showing the gap fin cooler. (b) Heat flux enhanced by upto 10% for nanofluids using exfoliated graphite particles in Poly Alpha Olefin oil (PAO) for concentrations of 0.6% and 0.3%. Inset: SEM of the precipitated nano-particles from the nanolfuid on to the heater surface leading to “nano-fin” effect which causes enhancement in heat flux (AIAA J. Thermophysics, 2008).

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Figure 7. Nanofluids in Compact Heat Exchangers. (a) Compact heat exchanger apparatus. (b) Heat flux enhanced by 30% for nanofluids using Carbon Nanotube (CNT) in Poly Alpha Olefin oil (PAO) for concentrations of 0.6%. Inset: Inset: SEM of the precipitated nano-particles from the nanolfuid on to the heater surface leading to “nano-fin” effect which causes enhancement in heat flux. (AIAA J. Thermophysics, 2008, in preparation)

Figure 8. Molecular Dynamics simulation of nanofins and nanofluids. (Inset) Unit cell with water and CuO nanoparticles in contact with nanofin. Interfacial resistance (Kapitza resistance) for water and CuO nanofluid changes in contact with the nanofluid. (Int. J. of Thermal Sciences, 2009)

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MICROFLUIDICS FOR BIO/NANO-LITHOGRAPHY

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Figure 9. Inkwells™: Microfluidic ink delivery apparatus for Dip Pen Nanolithography of 4-10 inks. (a) Inkwell for nano-bio lithography applications in genomics. (b), (c): Inkwell for nano-bio lithography applications in proteomics. (b), (c), (d) Scanning probes in registry with microwells for “ink-loading” step in DPN. (e) Computational results for meniscus bifurcation studies in capillary driven microfluidics. (SPIE J. of Micro/Nano-Fabrication, “MF3”, 2006).

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Figure 10. Centiwells: Microfluidic apparatus for simultaneous nano-patterning of ~100 species by Dip Pen Nanolithography (DPN). (a) SEM image of Centiwells containing polystyrene micro-beads. (b) Scanning probe on an Atomic Force Microscope dipped in PEG solution in the micro-wells. (c) LFM image of fractal nano-patterns formed by DPN of PEG. (SPIE J. of Micro/Nano-Fabrication, “MF3”, 2007).

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NANO-SENSORS FOR EXPLOSIVES DETECTION (HOMELAND SECURITY)

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Laser Source

Explosives Sensor

Detector

Laser Ray

Explosives Sensor (Nano-Calorimeter)

Micro-Heater (Gold)

Reaction Surface (Gold)

Activated Micro-Cantilever(Silicon Nitride)

Silicon Base

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Figure 11. (a) Schematic of explosive sensor using nano-calorimetry. (b) Micro-heaters maintain cantilevers at the ignition temperatures of the explosives to be detected.

In presence of an explosive the micro-cantilever at the corresponding ignition temperature is activated. Multiple cantilevers can be maintained at same temperature for eliminating false positives. Each micro-cantilever can be maintained at a specific temperature or scanned over a range of temperatures for detecting multiple explosives. Nominal dimensions Micro-cantilever: 150 × 25 microns, 100nm thick, Pitch: 30 microns; Micro Heaters: 25 × 22 microns, 100 nm thick, gold; Reaction surface: 10nm, gold.

Sensor Response (Summary)

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(a) (b) Figure 12. (a) Heated micro-cantilever array for explosives detection (by nano-calorimetry). Experimental results showing unique sensor response (signatures) under ambient conditions for several explosives: gasoline, acetone, alcohol. (Defense & Security Symp.’06, SPIE 6223-24).

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