Magnetohydrodynamic electrical power generation using convexly divergent channel: II. Numerical simulation

We describe quasi-three-dimensional numerical calculations based on large eddy simulation model for magnetohydrodynamic (MHD) electrical power generators equipped with modified wall configurations. The wall profile of the MHD channel is finely tuned in four types of geometry, that is, a concavely divergent channel, a linearly divergent channel, a convexly divergent channel and a highly convexed channel. The plasma-fluid properties and energy conversion efficiency are examined in detail. Although the deterioration in the plasma-fluid behaviour is not completely overcome, the advantages of the convexly divergent channel are notable. The convexly divergent channel exhibits the highest energy conversion performance, which is followed by the highly convexed, linearly and concavely divergent channels in order. The effect of the channel geometry modification on the generator performance is clearly quantified using a convexity parameter. This paper is the second part of a duology.