Characteristics of a disk MHD generator with inlet swirl

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:254626

Harada, Nob ^[1]; Okamura, T; Nakamichi, K; Noma, A ^[2]

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1. Nagaoka Univ. of Technology, Nagaoka (Japan)
2. Tokyo Institute of Technology, Yokohama (Japan)

Two kinds of experimental studies have been carried out to know the effect of inlet swirl in a disk type MHD generator. Firstly we decreased stagnation temperature in order to simulate a poor inlet plasma condition. Inlet swirl provided relatively higher radial Hall voltage and much better performance even for lower stagnation temperatures compared with those for simple radial flow case mainly due to the contribution of Faraday e.m.f. U{sub {theta}}B. High enthalpy extraction level near 30% could be kept even for lower stagnation temperatures in the range of 1600 K-1700 K. Secondary we decreased stagnation pressure to know generator performance under smaller pressure ratio of inlet to exit. Decrease of stagnation pressure improved enthalpy extraction very much unless increase of static pressure and decrease of Hall field became significant. Highest enthalpy extraction ratio of 38.2% was successfully achieved. From considerations of momentum balance along the radial direction, positive inlet swirl has important effect to reduce static pressure and also to reduce the unfavorable effect of Lorentz force. This suggests that introduction of inlet swirl is influential way to reach high isentropic efficiency.

• OSTI ID: 254626
• Report Number(s): CONF-950697--
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
DISK MHD GENERATORS
ENTHALPY
PERFORMANCE
PRESSURE GRADIENTS
SHOCK TUBES