As assessment of unseeded MHD accelerator using T-layer concept

The potential of applying the T-layer concept to flow acceleration is studied in this paper. Concentrations are on observing the performance assessment of a T-layer MHD accelerator using an unseeded plasma and on understanding the gasdynamics of T-layer interaction in the MHD channel. Argon is used as the working fluid to evaluate the potential advantages of using the nonequilibrium plasma in the T-layer MHD operating conditions. A one-dimensional unsteady model is developed to simulate the T-layer MHD flow accelerating process. This unsteady model is coupled with a criterion for the onset of non-equilibrium plasma. To support the results found from the unsteady model, the T-layer MHD generator modeling of Vasilyev is modified to describe the accelerator cases. Both models are applied to simulate a sample case with typical operating conditions of a T-layer accelerator with a single current layer, which is spontaneously inserted in the MHD channel. The results show that the flow is indeed accelerated by the T-layer MHD interaction and significant nonequilibrium effects in the plasma are obtained by both models. Certain level, but not serious, deviation is observed between the results obtained from the two models. The assumption of a constant load factor through the MHD accelerationmore » process is the major cause for the deviations. The unsteady model is then employed to simulate the complete process of a T-layer MHD accelerator including a T-layer formation section. Cases with single as well as multiple current layers in the channel are examined.« less