Spectral splitting solar energy transfer in small-diameter multimode optical fiber based on two-stage concentration

Abstract

A two-stage concentration system (TSC) is proposed for transfer spectral splitting solar energy via a small-diameter multimode optical fiber. The TSC includes a Fresnel lens that concentrates the energy before passing it through UV700 for spectral splitting. The system employs an optical fiber coupler for the second concentration stage and a single-diameter multimode fiber for energy transfer. We established a mathematical model of TSC, coupled optical fiber transmission, and analyzed it via simulation and experimentation. Simulation results demonstrate that the TSC reduces the spot's energy by 42% of the thermal radiation spectrum, decreases the focal spot radius by 58%, and improves the energy flux by 10.93 times with UV700. Additionally, experimental findings reveal that the TSC reduces the focal spot energy by 40.46% of the thermal radiation spectrum, decreases the fiber end temperature by 59.52%, identifies the optimal coupling distance at 308.75 mm, and yields a coupling efficiency of 60.7%.