MHD (magnetohydrodynamics) channel development: Quarterly report for October 1986-December 1986

Technical Report · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6044334

Both Faraday and diagonal loaded MHD generators have larger power outputs at high wall temperatures for all generator sizes investigated. The increase in power at high T/sub w/ diminishes with generator scale due to the drop in heat losses per unit volume as channels scale up. Boundary layer electrical detriments are volumetric effects and thus don't look too different when scaled to larger MHD generators. Voltage drops and axial shorting effects dominate at low wall temperature while velocity defects become important at high wall temperature. An experiment to investigate the effects of cathode resegmentation on the performance of an MHD generator controlled the cathode resegmentation effect by using externally shorted cathodes and by minimizing internal shorting by eliminating the ash injection. The data obtained from this experiment provide insights into the current flow within the shorted regions. The data also provides a qualitative understanding of the effect of cathode resegmentation on the internal electric fields and current densities. Review of the 86-SEED-6 test results indicates that a significant portion of the 1A channel power shortfall is associated with loss of Hall voltage. The Hall voltage loss may be coupled to axial current leakage in the slag layer as demonstrated during the post-power conductivity measurement test. The results of oil-fired and the coal-fired generator tests from the CDIF are compared. The axial leakage effects are much more dominant in the coal-fired tests. The shortfall in the performance of the coal-fired generator tests is the result of the increased leakage. Attempts are being made to identify and alleviate the various possible causes of this leakage. 15 refs., 78 figs.

• Research Organization: Avco-Everett Research Lab., Everett, MA (USA)
• DOE Contract Number: AC22-84PC70507
• OSTI ID: 6044334
• Report Number(s): DOE/PC/70507-11; ON: DE87014126
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
300101* -- MHD Generators-- Design & Development
CARBONACEOUS MATERIALS
COAL
COAL-FIRED MHD GENERATORS
DESIGN
DIRECT ENERGY CONVERTERS
ELECTRONIC CIRCUITS
ENERGY LOSSES
ENERGY SOURCES
FOSSIL FUELS
FUEL OILS
FUELS
HALL EFFECT
HEAT LOSSES
LIQUID FUELS
LOSSES
MATERIALS
MHD CHANNELS
MHD GENERATOR CDIF
MHD GENERATORS
OILS
ORGANIC COMPOUNDS
OTHER ORGANIC COMPOUNDS
PERFORMANCE TESTING
PETROLEUM PRODUCTS
POWER CONDITIONING CIRCUITS
TESTING