Parametric investigation of CuO-doped charged nanofluid in solar water heater

Global warming is increasing at an alarming rate nowadays, and to control its after effects is the most challenging task at present. Several steps have been undertaken to minimize its after effects, and in this direction, researchers have focused on the utilization of easily available renewable energy resources. In this perspective, solar energy stands out as a viable option. Solar energy utilization is one of the most attractive and efficient ways to utilize renewable resources for power generation and heating purposes. Nanomaterials generated through modern nanotechnology techniques have been employed which provides more efficient heat transfer and improvement in the performance of solar water heating. Nanocupric oxide (CuO) has been used for enhancement of heat transfer, thermal conductivity, thermal diffusivity of paraffin, and increment in the output temperature. But the presence of nanoparticles reduces the specific heat of paraffin. Field emission scanning electron microscopy and energy-dispersive X-ray (EDAX) have been used to examine the morphology of CuO nanoparticles, paraffin wax, and nano-CuO-paraffin composite. The maximum heat transfer rate and Rayleigh number are obtained as 5.7 KW and 8.84 × 107 pertaining to CuO nano-doped PCM composite while maintaining an air gap of 4 cm between the absorber plate and the glazing.