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Two-dimensional current distribution in Faraday type MHD energy conversion operating in the non-equilibrium conduction mode
ENERGYCONVERSION Summaries for Card Indexes W. T. PICCIANO, Space Power and Propulsion Department, Philco-Ford SRS Division,
Palo Alto, Calif. 94303, U.S.A. Determination of the solar cell equation parameters, indtullng series resistance, from empirical data: Energy Conversion 9, 1-6 (1969). Smnmary--Equations are derived to determine approximate values of the parameters in the conventional solar cell equation. The required experimental data consists of knowledge of three points to be taken from a single I-V curve: the short-circuit current, the open-circuit voltage, and the maximum power point. For data taken at extremes of temperature or intensity, the slope of the curve at the short-circuit point is also required. The approximate parameters may be subsequently improved by iteration. Two alternate equations are also derived which do not require knowledge of the maximum power point. These equations require information on four points along the I-V curve. The process readily produces reasonably accurate values of the cell series resistance, and the junction recombination factor. Key words: Solar cell maximum power point
I-V curve short-circuit current open-circuit voltage cell series resistance junction recombination factor
F. A. MORRISON JR, Department of Mechanical and Industrial Engineering, University of Illinois, Urbana, Illinois, U.S.A.; and J. F. OSTERLE, Department of Mechanical Engineering, Carnegie-Mellon University, Pittsburgh, Pennsylvania, U.S.A. A Unified treatment of the thermodynamics of sinnsoidal steady-state energy conver~don,
Energy Conversion 9, 7-12 (1969) Summary--Energy converters operating in the sinusoidal steady state are analyzed in detail. The classes of converters are considered. In each case, the maximum conversion ¢ffidency is determined and is given by two figures of merit. An illustrative example is presented. Key words: Two-part energy converter optimal operation output power
maximum efficiency
figure of merit
L. L. LENGYEL, Institut fiir Plasmaphysik, Gorching bei Miinchen, F. R,, Germany. Two-dime~ouai eurront distribution in Faraday type MI-ID ~ conversion operating in the non-equilibrium conduction mode, Energy Conversion 9, 13-23 (1969). Summary--In the first part of the paper, current and potential distributions in the plane normal to the applied magnetic field are considered with allowance for non-uniform gas temperature and velocity distributions, gas-dynamic convection, non-equilibrium ionization and finite rate relaxation processes. Quantitative data are provided regarding the magnitude of these effects on the performance characteristics of MHD energy converters. In the second part, the eddy currents induced in the plane normal to the flow direction are considered under open circuit conditions. It is shown that the effective open circuit voltage may be higher or lower than the value based on the average flow velocity--constant conductivity approximation depending upon the plasma parameter distributions in the insulator wall boundary layers. Key words: MHD energy converter(s) curtvnt distributions eddy currents voltage losses non-equilibrium ionization convective effects relaxation effects boundary layer effects stability considerations numerical analysis
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Palo Alto, Calif. 94303, U.S.A. Determination of the solar cell equation parameters, indtullng series resistance, from empirical data: Energy Conversion 9, 1-6 (1969). Smnmary--Equations are derived to determine approximate values of the parameters in the conventional solar cell equation. The required experimental data consists of knowledge of three points to be taken from a single I-V curve: the short-circuit current, the open-circuit voltage, and the maximum power point. For data taken at extremes of temperature or intensity, the slope of the curve at the short-circuit point is also required. The approximate parameters may be subsequently improved by iteration. Two alternate equations are also derived which do not require knowledge of the maximum power point. These equations require information on four points along the I-V curve. The process readily produces reasonably accurate values of the cell series resistance, and the junction recombination factor. Key words: Solar cell maximum power point
I-V curve short-circuit current open-circuit voltage cell series resistance junction recombination factor
F. A. MORRISON JR, Department of Mechanical and Industrial Engineering, University of Illinois, Urbana, Illinois, U.S.A.; and J. F. OSTERLE, Department of Mechanical Engineering, Carnegie-Mellon University, Pittsburgh, Pennsylvania, U.S.A. A Unified treatment of the thermodynamics of sinnsoidal steady-state energy conver~don,
Energy Conversion 9, 7-12 (1969) Summary--Energy converters operating in the sinusoidal steady state are analyzed in detail. The classes of converters are considered. In each case, the maximum conversion ¢ffidency is determined and is given by two figures of merit. An illustrative example is presented. Key words: Two-part energy converter optimal operation output power
maximum efficiency
figure of merit
L. L. LENGYEL, Institut fiir Plasmaphysik, Gorching bei Miinchen, F. R,, Germany. Two-dime~ouai eurront distribution in Faraday type MI-ID ~ conversion operating in the non-equilibrium conduction mode, Energy Conversion 9, 13-23 (1969). Summary--In the first part of the paper, current and potential distributions in the plane normal to the applied magnetic field are considered with allowance for non-uniform gas temperature and velocity distributions, gas-dynamic convection, non-equilibrium ionization and finite rate relaxation processes. Quantitative data are provided regarding the magnitude of these effects on the performance characteristics of MHD energy converters. In the second part, the eddy currents induced in the plane normal to the flow direction are considered under open circuit conditions. It is shown that the effective open circuit voltage may be higher or lower than the value based on the average flow velocity--constant conductivity approximation depending upon the plasma parameter distributions in the insulator wall boundary layers. Key words: MHD energy converter(s) curtvnt distributions eddy currents voltage losses non-equilibrium ionization convective effects relaxation effects boundary layer effects stability considerations numerical analysis
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