Determination of the single-phase forced convection heat transfer characteristics of TiO2nanofluids flowing in smooth and micro-fin tubes by means of CFD and ANN analyses

บทความในวารสาร

ผู้เขียน/บรรณาธิการ

กลุ่มสาขาการวิจัยเชิงกลยุทธ์

ไม่พบข้อมูลที่เกี่ยวข้อง

รายละเอียดสำหรับงานพิมพ์

รายชื่อผู้แต่ง: Kayaci N., Balcilar M., Tabatabaei M., Celen A., Yildiz O., Dalkilic A.S., Wongwises S.

ผู้เผยแพร่: Bentham Science Publishers

ปีที่เผยแพร่ (ค.ศ.): 2013

วารสาร: Current Nanoscience (1573-4137)

Volume number: 9

Issue number: 1

หน้าแรก: 61

หน้าสุดท้าย: 80

จำนวนหน้า: 20

นอก: 1573-4137

URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84875962442&partnerID=40&md5=4f943711ef83cebcda71d58d4ff48728

ภาษา: English-Great Britain (EN-GB)

บทคัดย่อ

A numerical study including a validation process with experimental data was performed on the forced convection flows of nanofluids; the object of study was water containing TiO2 nanoparticles in smooth and micro-fin tubes at a constant wall temperature. Constant heat flux and temperature-dependent properties were used to determine the hydrodynamics and thermal behaviors of the nanofluid flow;a single-phase numerical model was used to solve two-dimensional equations by means of a CFD program for the water flow, contained in a smooth tube and in various micro-fin tubes having various helix angles (0°, 18°). An extensive literature review on the determination of the physical properties (k, μ, ρ, Cp) of nanofluids is given in this paper. Multilayer Perceptron (MLP), one of the artificial neural network (ANN) methods, was used to determine the most agreeable physical properties of TiO2 nanofluids among correlations. The inputs of the ANN analyses were the correlations of physical properties, the average temperature and velocity of water in the test tubes, and the nanoparticle concentrations, while the outputs were shear stress, friction factor, heat flux, convective heat transfer coefficient, and pressure drop. After obtaining the best combination of physical properties of TiO2 nanofluids from the ANN analyses, the numerical model was validated by means of a CFD program, with the experimental smooth tube data as a case study; it was also validate-das a simulation study for several micro-fin tubes through a CFD program. This paper shows temperature, pressure, and velocity distributions in the investigated tubes; in addition, average and local experimental, theoretical, and numerical values in the smooth and micro-fin tubes are compared with one another in terms of friction factors, shear stresses, convective heat transfer coefficients, and pressure drops, according to various nanoparticle concentrations. © 2013 Bentham Science Publishers.

คำสำคัญ

ANN, CFD, Heat transfer coefficient, nanofluid, pressure drop, Single-phase flow