thermal energy storage, thermal management, vortex tubes, microfluidics
71
Scopus Publications
Scopus Publications
Experimental Investigation of Fin Distribution Effects on Single-Phase Flow in Micro-Pin-Finned Heat Sinks with Numerical Support Alperen Evcimen, Burak Markal, Mete Avci Micromachines, 2026 Technological development and thermal management are closely related, as chip-based units demand efficient cooling. Microchannel cooling is a key solution. This study, for the first time, experimentally and numerically investigates fin distributions with decreasing numbers, with/without staggered configurations, and the effect of dimples on single-phase flow in micro-pin-finned heat sinks. The database covers mass fluxes from 500 to 750 kg m−2 s−1 (in 50 increments) and four heat sinks (coded as MH-0, MH-1, MH-2, MH-3), with Reynolds numbers ranging from 234 to 327. Complementary numerical simulations were also employed to visualize flow structures and local Nusselt distributions to elucidate the experimental observations. It was concluded that low-velocity eddies occur in the dimples and between the successive pin-fins. The best thermal performance was obtained for MH-3, while the lowest pressure drop was measured for MH-1. Therefore, if heat transfer is the primary aim, MH-3 is preferred. MH-3 increases average Nusselt Number (Nuavg) by between 11.45% and 14.38% compared to MH-0. However, the pumping power results underline the importance of MH-1. Compared to MH-0, the pumping power decreases by up to 18.4% for MH-1, 16.6% for MH-2, and 13.8% for MH-3.
Non-Newtonian laminar pulsating heat and fluid flow in plane duct Ayse Nur Altunkaya, Orhan Aydin, Mete Avci Heat Transfer, 2024 In the present study, laminar pulsating power‐law momentum and heat transfer in a uniformly heated plane duct is studied analytically. Assuming that fully developed conditions exist both hydrodynamically and thermally, a perturbation series method is utilized to derive analytical solutions for the momentum and energy balance equations, and the amplitude is prescribed as the perturbation parameter. For varying values of the power‐law index (), representing pseudoplastic, Newtonian, and dilatant fluids, effects of dimensionless amplitude () and frequency () on periodic and period‐averaged friction factor and Nusselt number are obtained. The results obtained for Newtonian fluid are shown to be in good harmony with the corresponding findings in the open literature.
Pulsating flow and heat transfer of power-law fluid in a circular pipe Ayse Nur Altunkaya, Orhan Aydin, Mete Avci Nonlinear Analysis Modelling and Control, 2023 In this study, the pulsating flow of a non-Newtonian fluid and heat transfer in a pipe with uniform heat flux at its wall is examined analytically. The flow is assumed to be both hydrodynamically and thermally fully developed. The perturbation method based on the series expansion is used in the analysis. The periodic change and period-averaged values of the friction factor and Nusselt number as well as velocity and temperature profiles are obtained at varying values of dimensionless frequency and amplitude for shear-thinning, Newtonian and shear-thickening fluids. It is shown that the frequency is effective on the friction factor for a specific range of the dimensionless frequency. For some specific cases, excellent agreements are obtained with the literature. It is disclosed that the dimensionless frequency, the amplitude and the power-law index are interactively effective on the friction and heat transfer.
Effect of air change rate on particle dispersion from inlet opening under varying particle source strengths Yunus Emre Cetin, Mete Avci, Orhan Aydin International Journal of Ventilation, 2022 In this study, effect of air change rate (air change per hour – ACH) on indoor particle dispersion and deposition in a ventilated room is investigated. A reduced-scale model is designed to conduct experiments. Numerical predictions are performed by using the commercial software ANSYS Fluent 16.0. Four different values of the air change rate (1.73, 2.88, 5.76 and 7.68) and five different values of the particle diameter (0.181, 2.188, 4.42, 8.89 and 17.8 μm) are considered. Constant particle flow rate and proportional particle flow rate with inlet velocity cases are examined comparatively. Results show that, except from some inconsistencies for the largest particle diameter due to the accumulation and outlet opening location, the contaminant level decreases with increasing air change rate for a constant value of the particle flow rate while an opposite trend is observed for the proportional particle flow rate case.
Experimental study of single-phase fluid flow and heat transfer characteristics in rectangular microchannels Isi Bilimi Ve Teknigi Dergisi Journal of Thermal Science and Technology, 2018
Enhancing storage performance in a tube-in shell storage unit by attaching a conducting fin to the bottom of the tube Isi Bilimi Ve Teknigi Dergisi Journal of Thermal Science and Technology, 2018
Forced convection flow of viscous dissipative power-law fluids in a plane duct: Part 2. Thermally developing flow Isi Bilimi Ve Teknigi Dergisi Journal of Thermal Science and Technology, 2008
Forced convection flow of viscous dissipative power-law fluids in a plane duct: Part 1. Hydrodynamically and thermally fully developed flow Isi Bilimi Ve Teknigi Dergisi Journal of Thermal Science and Technology, 2008
