Comparative Analysis of Fluid Flow Attributes in Rectangular Shape Micro Channel having External Rectangular Inserts with Hybrid Al_2O_3+ZnO+H_2O Nano Fluid and (H_2O) Base Fluid

Abstract

: Comparative analysis is conducted between nano fluid (nf) Al 2 O 3 +ZnO+H 2 O and water (H 2 O) as base fluid through experimental and simulation result. The effect of nano fluid and (base) fluid flowing inside rectangular micro channel with or without insert were acknowledge, for analysis the behavior of fluid flow, heat transfer and performance characteristics like Nusselt number (Nu), Friction factor (f), Effectiveness (Ɛ), Coefficient of thermal transfer (h), Heat transfer factor (Q), Nu/Nus, f/fs, thermal-performance factor (TPF), Number of transferring unit (NTU) and Reynolds’s number (Re). During preparation of nano fluid 0.01% volume fraction, 10-20 nm size nano particles were taken with 0.5ml CTAB (cetyl-2 tri-methyl, ammonium-bromide) surfactant. Experimentation was conducted for different operating parameters under counter flow conditions, where nano fluid is flowing inside micro channel of 0.081mm diameter with flow rate 0.0001562 kg/sec (9.37 ml/min) to 0.006255 Kg/sec (375.30 ml/min) and hot water is flowing inside the concentric tube of 3cm diameter with flow rate of 0.000782 Kg/sec (46.92 ml/min). The operating temperature of nano fluid and hot water were 303K and 323K. As per obtained results, the proposed composition of nanofluid showed better performance than base fluid due to better thermal conductivity and extra molecular area gain in nanofluid due to addition of nano particle with base fluid. It improves the results 21% approximately. Better optimum results were observed in case of rectangular micro channel with micro insert compared with other geometry because of rich turbulency gain and extra exposed area due to micro insert. It affects optimum results in terms of better performance up to 9%-18% compared with simple micro channel without inserts.