Multi-field coupled analysis of thermal and opto-electrical conversion in InGaAs thermophotovoltaics

Based on near-realistic energy conversion and transport processes, a coupled model of an InGaAs thermophotovoltaic (TPV) cell is developed to analyze the influence of coupled behaviors and temperature-dependent properties from optical, electrical, and thermal perspectives. Under 2000 K blackbody radiation, with air- (20 W m- 2 K-1) and water-cooling (3000 W m- 2 K-1) conditions, it is observed that compared to the isothermal uncoupled model, the maximum output power shows a notable decline of 9.81 %. Furthermore, under different emitter temperatures, cooling conditions, and selective emissivity spectra, the thermal and electrical characteristics are examined to comprehensively evaluate TPV system performance. Increasing the emitter temperature improves system efficiency within an appropriate range. At an emitter temperature of 2000 K, the efficiency reaches a peak of 26.9 %. The intensity of air cooling has a minimal impact on system efficiency (0.03 %), whereas efficiency benefits significantly from enhanced water-cooling power (37 %), though the rate of improvement gradually diminishes. Additionally, as the selective emissivity spectrum broadens, the coupling behavior causes a significant decline of approximately 3 % in system efficiency, with the corresponding emissivity width decreasing by at least 100 nm. With the blueshift of selective emissivity, the efficiency increases monotonically, while the cell temperature peaks at 323.5 K.