Performance characteristics of a new hybrid solar cooker with air duct

A new hybrid solar box cooker (SBC) has been developed and tested for thermal performance evaluation in climatic condition of western Uttar Pradesh, India. The uniqueness of new box cooker is an integrated trapezoidal duct and its other integrated elements. The objective of the study is to enhance the heat transfer rate and to reduce the cooking timings by consumption of minimum heat energy. For this purpose, a 200 W halogen lamp has been placed inside the duct to enhance the heat transfer. Besides this, 450 of small hollow balls of copper have also been used to improve thermal performance of SBC especially on forced convection mode. The performances testing have been carried to evaluate the thermal efficiency, figures of merit (F1 and F2), cooking power, heat transfer and overall heat loss coefficient. After completion of experiments, thermal efficiency of SBC has been observed 45.11%, cooking power is estimated to be 60.20 W and overall heat loss coefficient is obtained around 6.01 W/m2 C. Results shows that the present design follow the BIS standards and can cook almost edibles in poor ambient conditions by consuming only 210 W. Discussion has also been made on the significance of the use of copper balls, fan and halogen lamp over the performance of SBC. The present solar cooker has been found as first kind of SBC which can efficiently perform on forced convection in any type of climatic conditions.