TPV efficiency predictions and measurements for a closed cavity geometry

Journal Article · Sat Mar 01 04:00:00 EST 1997 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.53284· OSTI ID:577814

Gethers, C K; Ballinger, C T; Postlethwait, M A; DePoy, D M; Baldasaro, P F ^[1]

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1. Lockheed Martin Corporation, Schenectady, New York (United States)

A thermophotovoltaic (TPV) efficiency measurement, within a closed cavity, is an integrated test which incorporates four fundamental parameters of TPV direct energy conversion. These are: (1) the TPV devices, (2) spectral control, (3) a radiation/photon source, and (4) closed cavity geometry effects. The overall efficiency of the TPV device is controlled by the TPV cell performance, the spectral control characteristics, the radiator temperature and the geometric arrangement. Controlled efficiency measurements and predictions provide valuable feedback on all four. This paper describes and compares two computer codes developed to model 16, 1cm{sup 2} TPV cells (in a 4{times}4 configuration) in a cavity geometry. The first code, subdivides the infrared spectrum into several bands and then numerically integrates over the spectrum to provide absorbed heat flux and cell electrical output performance predictions (assuming infinite parallel plates). The second code, utilizes a Monte Carlo Photon Transport code that tracks photons, from birth at the radiation source, until they either escape or are absorbed. Absorption depends upon energy dependent reflection probabilities assigned to every geometrical surface within the cavity The model also has the capability of tallying above and below bandgap absorptions (as a function of location) and can support various radiator temperature profiles. The arrays were fabricated using 0.55 eV InGaAs cells with Si/SiO interference filters for spectral control and at steady state conditions, array efficiency was calculated as the ratio of the load matched power to its absorbed heat flux. Preliminary experimental results are also compared with predictions. {copyright} {ital 1997 American Institute of Physics.}

• Sponsoring Organization: USDOE
• OSTI ID: 577814
• Report Number(s): CONF-9705119--
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 401; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
CAVITIES
COMPUTER CODES
COMPUTERIZED SIMULATION
EFFICIENCY
GEOMETRY
MONTE CARLO METHOD
PHOTON TRANSPORT
THERMOPHOTOVOLTAIC CONVERSION
THERMOPHOTOVOLTAIC CONVERTERS