Numerical Investigation to Study the Effect of Three Height of Triangular Obstacles on Heat Transfer of Nanofluids in a Microchannel.

As a following of scientific research that dealt with improving the thermal performance of thermal systems, this research means testing the overall performance of a thermal system by applying the effects of obstacles and the presence of nanoparticles in the flowing fluid. In a rectangular channel with three different-height triangular obstacles (4 µm, 6 µm, and 8 µm), a numerical study is conducted to examine the friction features and heat transfer enhancement for a 2D laminar flow and heat transfer. ANSYS Fluent 2022 has been used for the simulation. This work focuses on the use of nanoparticles (NPs), the existence of obstacles, and their impact on the thermal system's rate of heat transfer. The volume fraction of nano-particles (Ag) ranges from 2 to 6 percent, and their sizes are 25, 50, and 75 nm. With a NP diameter of 25 nm and an obstacle height of 8 µm, the results indicate that 6% is the optimal volume fraction, giving the largest values of heat transfer for all the obstacle heights tested. Experiments have also proved that increasing the flow velocity (increasing the value of the Reynolds number) gives the highest results for heat transfer. On the other hand, with regard to pressure drop, the values of Cf and obstacle height have been 8 µm and at 6% of volume fraction for all velocities. In addition, the presented result has been compared to previous results, and there has been a good agreement. [ABSTRACT FROM AUTHOR]