Experimental Study on the Influence of External Heat Flux and Air Pressure on the Combustion Characteristics of Solar Panels

High altitude region has different characteristics from the normal pressure region due to its low air pressure and low oxygen content. The aim of this study is to investigate how solar panel’s ignition time, critical heat flux, combustion time, flame height, and mass loss vary as a function of external heat flux from 25 kW/m² to 45 kW/m² and air pressure from 60 to 100 kPa. It was found that external heat flux and air pressure negatively correlated with ignition and combustion time. Calculated from Delichatsios’s formula, the critical heat flux under different air pressures differs significantly from experimental data. Therefore, the parameters in Delichatsios’s formula are corrected based on experimental data. By relating critical heat flux, thermal response parameters, and air pressure, an overall formula for ignition time, radiation intensity, and air pressure can be derived. Mass loss rate and flame height are positively correlated with external heat flux and air pressure. Mass loss rate is expressed as a function of air pressure. Also, based on the relationship between mass loss rate and external heat flux and air pressure, a mathematical model between flame height, heat flux and air pressure is established.