Numerical study on performance enhancement of the fin and tube heat exchanger using different nanoparticle shapes

The effects of various shapes of boehmite alumina nanoparticles including platelets, blades, cylindrical and bricks, mixed with water, on the thermo-economic characteristics of a fin tube heat exchanger (FTHE) are explored. Multi-objective optimization is applied for two objective functions including effectiveness and total annual cost (TAC). For this aim, nine design variables involving particle concentration are considered. Variations of nanofluid properties including viscosity, conductivity and Prandtl number versus particle volume fraction for various nanoparticle shapes are investigated. It is resulted that in the high range of effectiveness (e > 0.6), Pareto fronts of bricks shape are almost dominated on the other shapes of nanoparticles. It is also demonstrated that Pareto fronts of blades are completely captured on the other Pareto fronts in the fixed value of TAC for the region with medium effectiveness (0.4 < e < 0.6). Finally, the impacts of design parameters on the effectiveness are discussed for the optimum Pareto fronts.