Design optimization of staggered plates' channel heated by radiation heat flux based on the convective heat transfer and fluid flow for hybrid Photovoltaic/Thermal system

Optimization of configuration parameters based on the steady state convective heat transfer coefficient and friction factor for air flow inside a parallel plate channel with staggered plates heated by a radiation heat flux for combined photovoltaic and air heater solar collector systems (PV/T) are carried out. Temperatures of the solid boundary elements of flow field were obtained through using the ray-tracing technique to obtain the net absorbed fractions of the radiation heat flux the solid boundary surface elements. The model temperature results values were validated with measured temperature data and a good agreement prevailed. The model is used to investigate the optimization of configuration parameters of a parallel-plate channel with staggered plates based on the convective heat transfer coefficient (j), and friction factor (f) corresponds to the maximum value of the ratio of j/(f/2) within the flow Reynolds number ranging from 650 to 2550. The results show that: the optimum spacing of each staggered plate relative to nearest channel wall is around one-third of the channel height while the optimum (one) staggered plate length is ranging from 1.58 to 1.75 times the channel hydraulic diameter.