NANO-GÖZENEKLİ ZARLARDAN GERÇEKLEŞEN BUHARLAŞMANIN MOLEKÜLER DİNAMİK SİMÜLASYONLARI KULLANILARAK MODELLENMESİ

Öz

Nano-gözenekli yapılardan gerçekleşen buharlaşma, yüksek ısı akısına sahip elektronik cihazların ısıl yönetimindeki büyük potansiyeli nedeniyle teorik ve deneysel olarak geniş çapta incelenmektedir. Fakat moleküler/atomik seviye bir modelleme yönteminin eksikliği sebebiyle, sıvı-gaz arayüzeyinde gerçekleşen taşınımın temellerinin anlaşılabilmesi mümkün olamamaktadır. Bu çalışmada, uygun periyodik sınır koşullarının kullanımı sayesinde nano-gözenekli bir zarı betimleyebilen bir tekil nano-gözenekten gerçekleşen buharlaşmayı modelleyen bir hesaplama düzeneği oluşturulmuştur. Artan ısı yükleri altında, buharlaşan menisküsün şekli ve konumu gözlenmiş ve farklı buharlaşma rejimleri (çivilenmiş ve çekilen) tanımlanmıştır. Genel olarak bilinenin aksine, menisküsün çekilme sırasında kendi şeklini değiştirdiği keşfedilmiş ve bu duruma sebep olan fiziksel mekanizma açıklanmıştır. Nano-gözeneğin ısı uzaklaştırabilme kabiliyeti, farklı çalışma koşulları altında incelenmiştir. Yazarın bilgisine göre, bu çalışma, hem sıvı hem de buhar akışı ile ilgili olan sürekli-olmayan-ortam etkilerini göz önüne alarak nano-gözenekli bir zardan buharlaşmayı modelleyen ilk girişimdir. Sunulan yöntem, nano-gözenekli zarlardan gerçekleşen buharlaşmanın moleküler/atomik seviyede modellenebilmesinin önünü açmaktadır.

Anahtar Kelimeler

• Buharlaşma
• nano-gözenekli zar
• moleküler dinamik simülasyonu
• buharlaşan menisküsün kendi şeklini değiştirmesi

MODELING OF EVAPORATION FROM NANOPOROUS MEMBRANES USING MOLECULAR DYNAMICS SIMULATION

Öz

Evaporation from nanoporous structures is widely studied theoretically and experimentally due to its huge potential in thermal management of high heat flux electronic devices. Yet a fundamental understanding of liquid-vapor interfacial transport is lacking due to the absence of a molecular/atomic level modeling framework. In the current study, a computational setup is constructed to model the steady-state, continuous evaporation from a single nanopore, which is analogous to a nanoporous membrane due to the utilization of proper periodic boundary conditions. Under increasing heat loads, shape and position of the evaporating meniscus are observed, and different evaporation regimes (pinning and receding) are identified. An uncommon, self-regulation of the meniscus during receding is discovered and the underlying physical mechanism is elucidated. Heat removal ability of the nanopore is examined in response to different operating conditions. To the best of the author knowledge, the current study is the first attempt to model the evaporation from a nanoporous membrane incorporating non-continuum effects associated with the both liquid and vapor flows. The methodology presented opens up an avenue for the molecular/atomic level modeling of evaporation from nanoporous membranes.

Anahtar Kelimeler

• Evaporation
• nanoporous membrane
• molecular dynamics simulation
• self-regulation of an evaporating meniscus

Kaynakça

1. Akkuş Y., Tarman I. H., Çetin B. and Dursunkaya Z., 2017, Two Dimensional Computational Modeling of Thin Film Evaporation, Int. J. Therm. Sci., 121, 237-248.
2. Akkus Y. and Beskok A., 2019, Molecular Diffusion Replaces Capillary Pumping in Phase-change-driven Nanopumps, Microfluid. Nanofluid., 23, 14.
3. Akkus Y., Nguyen C. T., Celebi A. T. and Beskok A., 2019, A First Look at the Performance of Nano-grooved Heat Pipes, Int. J. Heat Mass Trans., 132, 280-287.
4. Barisik M. and Beskok A., 2011, Molecular Dynamics Simulations of Shear-driven Gas Flows in Nano-channels, Microfluid. Nanofluid., 11, 611-622.
5. Barisik M. and Beskok A., 2013, Wetting Characterisation of Silicon (1, 0, 0) Surface, Mol. Simul., 39, 700-709.
6. Barker J. A. and Pompe A., 1968, Atomic Interactions in Argon, Aust. J. Chem., 21, 1683-1694.
7. Cai Q. and Bhunia A., 2012, High Heat Flux Phase Change on Porous Carbon Nanotube Structures, Int. J. Heat Mass Tran., 55, 5544-5551.
8. Caupin F. and Herbert E., 2006, Cavitation in Water: A Review, C. R. Phys., 7, 1000-1017.

9. Cheng L., Fenter P., Nagy K. L., Schlegel M. L. and Sturchio N. C., 2001, Molecular-scale Density Oscillations in Water Adjacent to a Mica Surface, Phys. Rev. Lett., 87, p.156103.
10. Ćoso D., Srinivasan V., Lu M. C., Chang J. Y. and Majumdar A., 2012, Enhanced Heat Transfer in Biporous Wicks in the Thin Liquid Film Evaporation and Boiling Regimes, J. Heat Transf., 134, p.101501.
11. Ding C., Soni G., Bozorgi P., Piorek B. D., Meinhart C. D. and MacDonald N. C., 2010, A Flat Heat Pipe Architecture Based on Nanostructured Titania, J. Microelectromech. S., 19, 878-884.
12. Dullien F. A. L., 1992, Porous Media: Fluid Transport and Pore Structure, 2nd ed., Academic Press. Fisher J. C., 1948, The Fracture of Liquids, J. Appl. Phys., 19, 1062-1067.
13. Foiles S. M., Baskes M. I. and Daw M. S., 1986, Embedded-atom-method Functions for the Fcc Metals Cu, Ag, Au, Ni, Pd, Pt, and Their Alloys, Phys. Rev. B, 33, p.7983.
14. Gambill W. R. and Lienhard J. H., 1989, An Upper Bound for the Critical Boiling Heat Flux, J. Heat Transf., 111, 815-818.
15. Garimella S. V., Fleischer A. S., Murthy J. Y., Keshavarzi A., Prasher R., Patel C., Bhavnani S. H., Venkatasubramanian R., Mahajan R.,
16. Joshi Y. and Sammakia B., 2008, Thermal Challenges in Next-generation Electronic Systems, IEEE Transactions on Components and Packaging Technologies, 31, 801-815.
17. Ghorbanian J., Celebi A. T. and Beskok A., 2016, A Phenomenological Continuum Model for Force-driven Nano-channel Liquid Flows, J. Chem. Phys., 145, p.184109.
18. Guo C., Yu D., Wang T., Jiang Y. and Tang D., 2015, Theoretical and Experimental Analysis of the Evaporating Flow in Rectangular Microgrooves, Int. J. Heat Mass Trans., 84, 1113-1118.
19. Heslot F., Fraysse N. and Cazabat A. M., 1989, Molecular Layering in the Spreading of Wetting Liquid Drops, Nature, 338, 640-642.
20. Lee J., Laoui T. and Karnik R., 2014, Nanofluidic Transport Governed by the Liquid/vapour Interface, Nature Nanotechnol., 9, 317-323.
21. Lu Z., Narayanan S. and Wang E. N., 2015, Modeling of Evaporation from Nanopores with Nonequilibrium and Nonlocal Effects, Langmuir, 31, 9817-9824.
22. Lu Z., Wilke K. L., Preston D. J., Kinefuchi I., Chang-Davidson E. and Wang E. N., 2017, An Ultrathin Nanoporous Membrane Evaporator, Nano Lett., 17, 6217-6220.
23. Maroo S. C. and Chung J. N., 2010, Heat Transfer Characteristics and Pressure Variation in a Nanoscale Evaporating Meniscus, Int. J. Heat Mass Trans., 53, 3335-3345.
24. Maruyama S. and Kimura T., 1999, A Study on Thermal Resistance over a Solid-liquid Interface by the Molecular Dynamics Method, Therm. Sci. Eng., 7, 63-68.
25. Moosman S. and Homsy G. M., 1980, Evaporating Menisci of Wetting Fluids, J. Colloid Int. Sci., 73, 212-223.
26. Narayanan S., Fedorov A. G. and Joshi Y. K., 2011, Interfacial Transport of Evaporating Water Confined in Nanopores, Langmuir, 27, 10666-10676.
27. Nguyen C. T. and Beskok A., 2018, Saltwater Transport through Pristine and Positively Charged Graphene membranes, J. Chem. Phys., 149, p.024704.
28. Nie X., Hu X. and Tang D., 2013, Modeling Study on Axial Wetting Length of Meniscus in Vertical Rectangular Microgrooves, Appl. Therm. Eng., 52, 615-622.
29. Nilson R. H., Tchikanda S. W., Griffiths S. K. and Martinez M. J., 2006, Steady Evaporating Flow in Rectangular Microchannels, Int. J. Heat Mass Trans., 49, 1603–1618.
30. Palko J. W., Zhang C., Wilbur J. D., Dusseault T. J., Asheghi M., Goodson K. E. and Santiago J. G., 2015, Approaching the Limits of Two-phase Boiling Heat Transfer: High Heat Flux and Low Superheat, Appl. Phys. Lett., 107, p.253903.
31. Peng B., He W., Hao X., Chen Y. and Liu Y., 2014, Interfacial Thermal Conductance and Thermal Accommodation Coefficient of Evaporating Thin Liquid Films: A Molecular Dynamics Study, Comp. Mater. Sci., 87, 260-266.
32. Plawsky J. L., Fedorov A. G., Garimella S. V., Ma H. B., Maroo S. C., Chen L. and Nam Y., 2014, Nano-and Microstructures for Thin-film Evaporation—A Review, Nanosc. Microsc. Thermophys. Eng., 18, 251-269.
33. Plimpton S., 1995, Fast Parallel Algorithms for Short-range Molecular Dynamics, J. Comput. Phys., 117, 1-19. Pop E., 2010, Energy Dissipation and Transport in Nanoscale Devices, Nano Res., 3, 147-169.
34. Scholander P. F., Bradstreet E. D., Hemmingsen E. A. and Hammel H. T., 1965, Sap Pressure in Vascular Plants: Negative Hydrostatic Pressure can be Measured in Plants, Science, 148, 339-346.
35. Shi Z., Barisik M. and Beskok A., 2012, Molecular Dynamics Modeling of Thermal Resistance at Argon-graphite and Argon-silver Interfaces, Int. J. Therm. Sci., 59, 29-37.
36. Stephan P. C. and Busse C. A., 1992, Analysis of the Heat Transfer Coefficient of Grooved Heat Pipe Evaporator Walls, Int. J. Heat Mass Trans., 35, 383-391.
37. YD S. and Maroo S. C., 2016, Origin of Surface-driven Passive Liquid Flows, Langmuir, 32, 8593-8597.
38. Vo T. Q., Barisik M. and Kim B., 2015, Near-surface Viscosity Effects on Capillary Rise of Water in Nanotubes, Phys. Rev. E, 92, p.053009.
39. Wayner P.C., Kao Y. K. and LaCroix L. V., 1976, The Interline Heat-transfer Coefficient of an Evaporating Wetting Film, Int. J. Heat Mass Trans., 19, 487-492.
40. Weibel J., Garimella S. V., Murthy J. Y. and Altman D. H., 2011, Design of Integrated Nanostructured Wicks for High-Performance Vapor Chambers, IEEE Transactions on Components Packaging and Manufacturing Technology.
41. Wheeler T. D. and Stroock A. D., 2008, The Transpiration of Water at Negative Pressures in a Synthetic Tree, Nature, 455, 208-212.
42. Wilke K. L., Barabadi B., Lu Z., Zhang T. and Wang E. N., 2017, Parametric Study of Thin Film Evaporation from Nanoporous Membranes, Appl. Phys. Lett., 111, p.171603.
43. Xiao R., Maroo S. C. and Wang E. N., 2013, Negative Pressures in Nanoporous Membranes for Thin Film Evaporation. Appl. Phys. Lett., 102, p.123103.
44. Yu J. and Wang H., 2012, A Molecular Dynamics Investigation on Evaporation of Thin Liquid