Study On Numerical Simulation Of The Heat Transfer And Flow Characteristics Of Polymeric-fluid-Based Cu Nanofluids

With the development of the heat exchange technology, the better the performanceof materials are, the more can satisfy people’s request. It is imperative to find new fluidwith a good heat carrying ability and low energy loss. Nanofluids has a broadapplication prospects for its good heat transfer performance，stability, not easily towear down and block the pipeline. Adding polymer to water can achieve the effect ofreducing resistance loss in the flow greatly, It has been broadly used in fluid distributionsystem. Polymer brought some drag reduction effect to solution, at the same time,however, the heat transfer of the solution is reduced, so there were still some limitationsin practical application. Therefore combining the effect of drag reduction and heattransfer enhancement together in order to form a new kind of flow and heat transferliquid Polymeric-fluid-based nanofluids, which is a good reference to practicalengineering applicationThe purpose of this paper is to study the heat transfer and flow characteristics ofthe nanofluids and polymeric fluid, and the nanoparticles’higher thermal conductivitycan solve the problem that polymeric fluid has the disadvantage of heat transferreduction. The heat transfer and flow characteristic of the solution such as Cunanofluids, polymeric fluid and polymeric-fluid-based Cu nanofluids have beensimulated numerically by Fluent6.2.3. Through calculation and analysis, It can obtainthat:Under the forced convective condition, adding a small amount of nanoparticles towater can significantly enhance the solution’s heat transfer, however, It has been of nouse to improve the heat transfer by continuing adding more nanoparticles. In theLaminar flow, the best heat transfer volume fraction of nanofluids is1%; while inturbulence flow, the best heat transfer volume fraction of nanofluids is0.5%; The higherReynolds number is, the better heat transfer effect can be enhanced, while increasing theheat flux can do little contribution to it. In addition, a comparative study of DPM（Discrete phase model） and single phrase model was performed, The resultsindicates that forces in the fluid have some effect on the velocity field while have noeffect on the temperature field with the same Reynold.The results under the turbulence condition shows that polymeric fluid have theeffects of drag reduction and heat transfer reduction compared with the Newtonian fluid.The higher Reynold is, the better effect of drag reduction will have, when Reynoldsnumber is20000, the rate of drag reduction is61.04%, and the heat transfer reductionrate is45.88%;That is because the polymeric fluid have a lower stress than Newtonian fluid, and the outer layer of the dimensionless velocity and temperature in the polymericfluid flow became thicker which can also fully explain the reason of drag reduction andheat transfer reduction phenomenon.Polymeric-fluid-based Cu nanofluids had been simulated and calculatednumerically on the basis of numerical simulation of nanofluids and polymeric fluid. Theresults indicates that the addition of nanoparticles slightly increase the flow drag, andenhance the heat transfer of the fluid to a certain extent; Secondly Reynolds number isthe key factor in enhancing the heat transfer and the total wall shear stress of the fluid;Furthermore, the total wall shear stress and Nu decrease with the increase of dragparameter which can fully explain that in polymeric-fluid-based Cu nanofluids polymerstill play an important role in drag reduction and heat transfer reduction.