Abstract
Using single layer microchannels accompanied by nanofluids is one of the most practical solutions in thermal management of high power density devices. The main challenge in cooling systems of electronic devices is to provide a uniform temperature distribution. In the present study, fluid flow and heat transfer in a fractal microchannel heatsink have been simulated employing the computational fluid dynamics (CFD) method. The fractal microchannel is used to achieve uniform temperature distribution. Thermal performance of single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) dispersed in the two base fluids of water and kerosene in a fractal microchannel at Reynolds (Re) numbers of 1500 to 3000 are investigated. It should be noted that the nanofluids have been simulated by the two-phase mixture model. The results indicated that the use of fractals silicon microchannel leads to having a uniform temperature distribution. Based on the results, at maximum Re number when the working fluid is water, Nu number and pumping power are 20.9 and 0.033 W whereas, in kerosene flow at the same condition, Nu number and pumping power are 6 and 0.054 W, respectively. According to the obtained results, using the SWCNT nanoparticle compared with the MWCNT nanoparticle leads to a significant enhancement in the Nusselt (Nu) number. This difference is more pronounced by increasing the Re number and nanoparticle volume fraction. In addition, the results indicated that at the same Re number and nanoparticle volume fraction, the performance evaluation criterion of the water-based nanofluid is 4 times higher than that of the kerosene-based nanofluid. So the use of the water as the working fluid with the SWCNT nanoparticle for cooling in the fractal silicon microchannel is recommended.
Highlights
Nowadays, the increase in heat transfer rate in various applications and devices, especially high-power density electronic devices, has become an important issue[1,2,3,4]
The temperature difference between the wall and fluid decreased along the path, which leads to reducing the heat transfer rate
In the present numerical study, the heat transfer and fluid flow were simulated in a fractal microchannel with two working fluids of water and kerosene suing single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) nanoparticles in different solid volume fractions ranging from 0 to 8 vol % employing finite volume method
Summary
The increase in heat transfer rate in various applications and devices, especially high-power density electronic devices, has become an important issue[1,2,3,4]. Xu et al.[34] studied the effect of pulsation on the flow and heat transfer in the fractal silicon microchannel network using numerical simulation and experimental data They presented local Nusselt Number (Nu) distribution, temperature distribution, and pressure loss in different Reynolds numbers (Re). Zhang et al.[36] numerically and experimentally investigated the effects of S-type and straight fractal-like microchannel on the fluid flow and heat transfer characteristic They compared the results of experiments with those of simulations employing the conventional equivalent and subsectional integral methods and found that the developed subsectional integral method has better performance to predict the friction factor and Nusselt number compared to other methods.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
