Investigating the Effect of Cuo Nano particles Concentration and Reynolds Number on a Number of Properties Related to Heat Transfer in Non-Newtonian Fluid (water + CMC)

In this research, non-Newtonian nanofluid (water + CMC) / Cuo with volume percentages (۰.۵, ۱, ۱.۵, ۳ and ۴) in a tube under constant thermal flux has been simulated using fluent software. The base fluid in this research is a combination of water and ۰.۵% by weight of CMC (chloromethyl cellulose), which gives water a non-Newtonian property . First, an attempt was made to determine the necessary properties for simulation, such as viscosity, thermal conductivity, density and specific heat capacity. In the modelling stage, the properties of the non-Newtonian nanofluid (water +CMC) / Cuo were determined in the mentioned volume percentages. The viscosity and thermal conductivity coefficient of nanofluid are highly dependent on temperature. Of course, apart from temperature, the viscosity of nanofluid is also a function of shear rate. The experimental figures of viscosity and thermal conductivity are taken from the articles. These figures are discrete and not presented as a function. Therefore, before the simulation stage, in the modelling stage, continuous functions were determined for these two parameters. The modelling results are in good agreement with the experimental results. Density and specific heat capacity are assumed to be constant in a certain volume percentage. After modelling the movement of the mentioned nanofluids in slow flow (Re=۶۰۰, ۹۰۰, ۱۲۰۰, ۱۵۰۰) and in a pipe under constant thermal flux, it is simulated with a uniform velocity at the entrance of the pipe. Finally, changes in important heat transfer parameters such as displacement heat transfer coefficient and average Nusselt number were investigated in different Reynolds numbers and for different volume percentages of the mentioned nanofluids.

کلیدواژه ها:

Modelling ، Simulation ، Non-Newtonian ، Nano-fluid ، CMC (Chloromethyl Cellulose