On the effect of structural forces on a condensing film profile near a fin-groove corner

Date

2020-07-01

Author

Akdag, Osman
Akkus, Yigit
Dursunkaya, Zafer

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

85
views

0
downloads

Estimation of condenser performance of two-phase passive heat spreaders with grooved wick structures is crucial in the prediction of the overall performance of the heat spreader. Whilst the evaporation problem in microgrooves has been widely studied, studies focusing on the condensation on fin-groove systems have been scarce. Condensation on fin-groove systems is actually a multi-scale problem. Thickness of the film near the fin-groove corner can decrease to nanoscale dimensions, which requires the inclusion of nanoscale effects into the modeling. While a few previous studies investigated the effect of dispersion forces, the effect of structural forces has never been considered in the thin film condensation modeling on fin-groove systems. The present study utilizes a disjoining pressure model which considers both dispersion and structural forces. The results reveal that structural forces are able to dominate dispersion forces in certain configurations. Consequently, by intensifying the disjoining pressure, structural forces lead to a sudden change of the film profile (slope break) for subcooling values which are relevant to engineering applications.

Subject Keywords

Atomic and Molecular Physics, and Optics, General Chemical Engineering, Condensed Matter Physics

URI

https://hdl.handle.net/11511/46271

Journal

INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER

DOI

https://doi.org/10.1016/j.icheatmasstransfer.2020.104686

Collections

Department of Mechanical Engineering, Article

Suggestions

OpenMETU
Core

A theoretical study of chemical doping and width effect on zigzag graphene nanoribbons Pekoz, Rengin; Erkoç, Şakir (Elsevier BV, 2009-12-01) The energetics and the electronic properties of nitrogen- and boron-doped graphene nanoribbons with zigzag edges have been investigated using density functional theory calculations. For the optimized geometry configurations, vibrational frequency analysis and wavefunction stability tests have been carried out. Different doping site optimizations for a model nanoribbon have been performed and formation energy values of these sites revealed that zigzag edgesite for both of the dopants were the most favorable ...
On the theory of internal photoemission in heterojunctions Aslan, B; Turan, Raşit (Elsevier BV, 2005-08-01) The theory of internal photoemission in semiconductor heterojunctions has been reviewed and the existing model has been extended by incorporating the effects of the difference in the effective masses in the active region and the substrate, non spherical-nonparabolic bands, and the energy loss per collisions. This complete model has been applied to describe the experimental results obtained from Si1-xGex/Si heterojunction infrared photodetectors. The barrier heights (correspondingly the cut-off wavelengths) ...
On the electrical and charge conduction properties of thermally evaporated MoOx on n- and p-type crystalline silicon GÜLNAHAR, MURAT; Nasser, Hisham; Salimi, Arghavan; Turan, Raşit (Springer Science and Business Media LLC, 2020-11-01) In this work, the electrical and charge conduction characteristics of a contact structure featuring thermally evaporated MoOx, deposited on n- and p-type crystalline silicon (c-Si), are extensively investigated by room temperature current-voltage (I-V), transmission line measurements (TLM), and temperaturedependent current-voltage measurements (I-V-T). XRD diffraction spectrum shows that the deposited MoOx film exhibits amorphous nature. From TLM measurements, the values of contact resistivity are calculate...
Evaluation of the radiative recombination mechanism in Si nanocrystals embedded in silica matrix Righini, Marcofabio; Gnoli, Andrea; Razzari, Luca; Serincan, Ugur; Turan, Raşit (American Scientific Publishers, 2008-02-01) We report measurements of the temperature dependence of photoluminescence (PQ life-time and efficiency of Si nanocrystals (Si-Nc) embedded in silica matrix. We use a practical technique based on lock-in acquisition that allows us to simultaneously evaluate, at each emission-energy, intensity and decay-time of the detected signal. Samples are prepared by Silicon-ion implantation in a SiO2 layer followed by thermal annealing. The implantation dose of Si ions ranges between 2 x 10(16) cm(-2) and 2 x 10(17) cm(...
Analysis of the Specific Heat in the Supercooled Solid Phase of Liquid Crystals Kilit, Emel; Yurtseven, Hasan Hamit (Informa UK Limited, 2011-01-01) The specific heat Cp is analyzed using the experimental data at various temperatures in the solid phase of cholesteryl myristate according to a power-law formula for the rapidly and slowly cooled solid in the stability limit. We also analyze the temperature dependence of the Cp using the experimental data for the supercooled solid phase of p-azoxyanisole in the stability limit and the stability temperatures are determined for both cholesteryl myristate and p-azoxyanisole.

Citation Formats

O. Akdag, Y. Akkus, and Z. Dursunkaya, “On the effect of structural forces on a condensing film profile near a fin-groove corner,” INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER, pp. 0–0, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/46271.