Low-frequency vibration for fouling mitigation and intensification of thermal performance of a plate heat exchanger working with CuO/water nanofluid

In the present work, experimental investigation is performed on the thermal performance of a chevron type flat plate heat exchanger working with CuO/water nanofluid with the especial emphasis on the fouling formation of nanoparticles inside the heat exchanger. Over a transient study, low frequency vibration was implemented to mitigate the fouling of nanoparticles inside the heat exchanger. To investigate the influence of fouling formation on the thermal performance of the system, fouling thermal resistance parameter was defined. Results showed that fouling of nanoparticles can be mitigated via low frequency vibration and fouling thermal resistance is decreases by applying the vibration into the system. Likewise, overall thermal performance of the system is intensified, when vibration is continuously applied into the heat exchanger. In the absence of vibration, fouling of particles is continually formed on the inner walls of the heat exchanger, which causes a thermal resistance. More importantly, fouling layer apparently can enhance the roughness, friction factor and the pressure drop inside the heat exchanger. In addition, it was found that there is an optimum point for the concentration of particles, which in this study was wt.% = 0.3 for CuO/water nanofluid. Frequency and amplitude of the vibration waves were found to increase the thermal performance of the heat exchanger. (C) 2017 Elsevier Ltd. All rights reserved.