Design And Performance Analysis Of The Thermophotovoltaic System Based On Automobile Exhaust Heat

Along with the deepening of theoretical research and rapid progress of modernmicrofabrication technology, photonics experiencing unprecedented development resulting inmany new interdisciplines and emerging research directions, nanophotonics is one of theproducts. The main study of nanophotonics are the interaction law between light and matter inmicro and nano scales and the applications in light generation, spectrum control, transmission,sensing, detection and so on.Since automobile exhaust owns tremendous energy and causing serious environmentaltherma pollution, according to the response scope and efficiency of photovoltaic cells havebeen reported selecting InAsSbP/InAs PV cell with3.2μm forbidden band wavelength makinguse of exhaust heat to generate power, designed filter and selective radiator matched withselected PV cell to achieve spectrum control of TPV system in this paper.Designing a one dimensional Si-SiO₂photonic crystal filter of （LH）4type based onelectromagnetic theory, simulation results showed that the structure forms high reflective bandin3.2⁶.2μm and high transmission band in1.59³.2μm, which can achieve the spectralcontrol of selected PV cells. However, there are many oscillations and high reflection peakswithin the passband, then optimize designing the type of L/2H（LH）3and1.12（L/2HL/2）（L/2HL/2）21.16（L/2HL/2） filters based on the principle of reflective layers andthe equivalent index method of dielectric layers to solve these problems. They have much lessoscillations and lower reflection peaks within the passband and greatly improved theperformance of filter. Next analyzing the affect of various parameters on spectral control toprovide a reference for the actual fabrication and application. Then preparing the filter samplesfor the experiment using magnetron sputtering technique, the results is agree well withtheoretical simulations. At last calculating the energy distribution of blackbody radiationspectrum going through the designed filter and spectral control efficiency, it is higher25%onaverage compared with no filter.At first, analyzing surface plasmon resonance and magnetic polarization resonancecharacteristics of the micro-structure gratings, and then designing a3.2μm wavelengthAu-Si-Au-Si-Au grating selective radiator, the FWHM is0.7μm and have no directionselectivity. Further optimize designing Ag-SiO₂-Ag grating radiator, the radiation curve of thestructure at the boundary wavelength is steeper, it has stronger selective radiation, more convenient processing and cheaper costing, and it’s FWHM is0.45μm. Predicting the magneticresonance condition by using of the equivalent LC circuit model, the results agree well withFDTD simulation results. Finally calculating the spectral control efficiency of the designedselective radiator, it is higher43%on average compared with blackbody radiator.If using designed selective radiator combined with filter, the TPV thermoelectricconversion efficiency is up to15.8%as the temperature is1200K. If the research of the PV cellis more mature and the efficiency is higher, this technology would expect to become a reality, itis very important for saving renewable energy and improving environmental thermal pollution.