Fundamental Performance of Disk-shaped Magnetohydrodynamics Accelerator

Abstract

This paper investigates the acceleration performance of a disk-shaped magnetohydrodynamics (MHD) accelerator. Quasi-1-dimensional (Q1D) numerical simulation employing the MacCormack scheme was developed. For the longer channel length of 0.9 m, thermal loss was estimated at over 60% and effective acceleration could not be achieved owing to large heat loss and large friction loss. For shorter channel lengths, thermal loss can be reduced below 20% owing to the smaller heat and the friction losses. However, with too short a channel length, accelerator performance was decreased by the MHD compression due to excessive Faraday current density. The effect of ratio of cross sectional area on performance was also studied. For a larger area ratio, the gas can be accelerated smoothly throughout the MHD channel. However, for the excessive expansion case of a sevenfold channel, gas velocity near the exit decreased due to transition to a ''generator mode''. For the best acceleration performance, the design channel length should be as short as possible preventing compression at the channel inlet. The area ratio should be large enough to prevent the compression but not too large, to prevent transition to a ''generator mode''.

On heat and mass transfer analysis for the flow of a nanofluid between rotating parallel plates

“…Cha et al and Tneakeshita et al [15,16] presented some important theoretical ideas to understand the working of cooling systems by using liquid metals in magneto hydro dynamic generators, accelerators, pumps and flow meters. The relation of heat transmission with Hartman and Rayleigh numbers was recorded by Sheikholeslami et al [17].…”

The Effect of Magnetic Nozzle for Disk Magnetohydrodynamics Accelerator

“…This MHD bypass system is quite simply principle and useful because part of MHD accelerator can generate considerably high acceleration and high speed of gas (plasma) due largely to the interaction of the working gas and the applied magnetic field as supplying the electric field (extracted energy from MHD generator part). It is found that most of the currently published works are focused on the linear MHD accelerator [1]- [8], however we have been focusing on the disk MHD accelerator since 2005 [9], [12]- [13].…”