Thermal performance analysis of mechanical draft cooling tower filled with rotational splash type packing by using nanofluids

In this study, effects of using nanofluid (distilled water as base fluid and aluminum oxide and copper oxide as nanoparticles) on thermal performance of mechanical draft cooling tower have been experimentally investigated and results have been compared with performance of the tower in presence of pure water. A counter flow wet cooling tower with non-uniform and rotational splash type packing has been used. Experiments have been carried out to investigate the effects of inlet temperature of nanofluid, concentration and type of nanofluid, and mass flow ratio of working fluid to air (L/G) on the thermal performance of the cooling tower. Preparation of the nanofluid has been accomplished in two-step method, by adding sodium dodecyl benzenesulfonate surfactant to improve the dispersion of particles and stability of suspension. Present results show that by using nanofluid, thermal performance of the cooling tower improved, and this improvement varies depending on inlet temperature of nanofluid, type and concentration of nanofluid. For instance, with an increase in the inlet temperature of aluminum oxide/water nanofluid (0.1 wt%) from 37.5 to 42.5 degrees C, effectiveness of the tower increased by 11%. However, using pure water with the same conditions, the effectiveness increased about 8.5%. Furthermore, by increasing the concentration of this nanofluid from 0 to 0.15 wt%, the effectiveness increased about 7.2%. Finally, by using copper oxide/water nanofluid, performance of the cooling tower improved with effectiveness about 5%.