IMPROVEMENT OF PLASMA MHD GENERATOR PERFORMANCE BY OPTIMIZATION OF CHANNEL GEOMETRY

当前研究的目标是对等离子体MHD发生器性能的改进，这些等离子体MHD发生器希望提供非常高的热效率;在1997年财政部，对一个区域比率在一个孤立效率和一个封闭的提取之间的关系的影响是被调查的实验的，而且对区域比率的优化也是产生的。作为一个结果，最高的同步效率得到了实现，达到了46.5%。在同一时间，140兆瓦/米的最高功率密度为13-D1被演示。该实验表明，对商用发电厂的高同步效率要求是唯一可能的磁盘MHD发生器与小面积比率有关。1998年财政部采用的一个介绍，以改善入口提取物。一个新的概念被采纳为螺旋货车的设计，并在订购设计螺旋货车时，采用了三个维度的数字模拟。根据这个模拟，瘦的漩涡面包车是有用的，可以减少流体动力学损失。在实验中，入口卷曲的提取物得到了极大的改善，作为一个结果，最高的三分之一效率提高到54.3%。这是等离子体MHD发生器中的最高点。1999年财政部，MHD发生器中的流动场和等离子体行为被调查，并收集了大量重要数据。数据提出了一个大的正螺旋桨和一个高的马赫数保持在MHD发生器中，并且这一线索达到了高的同时性效率。目前的研究已经证明了我们将在比目前的成员更高性能的成就中迈出的下一步是主要的目标。

The objective of present study is an improvement on performance of the plasma MHD generator which is expected to provide very high thermal efficiency.In fiscal 1997, effects of an area ratio on a relation between the isentropic efficiency and the enthalpy extraction were investigated experimentally and an optimization of the area ratio was also made. As a result, the highest isentropic efficiency was achieved and it was 46.5 %. At the same time, the highest power density of 140 MW/mィイD13ィエD1 was demonstrated. The experiments have indicated that a high isentropic efficiency required for a commercial power plant is possible only for the Disk MHD generator with a small area ratio.An introduction of an inlet swirl was adopted in fiscal 1998 in order to improve the enthalpy extraction. A new concept was adopted to the design of the swirl vane, and in order to design the swirl vanes, three-dimensional numerical simulation was carried. The simulation indicated that thin swirl vanes are useful to reduce fluid-dynamical loss. In the experiments with the inlet swirl, the enthalpy extraction was improved remarkably and as a result, the highest isentropic efficiency increased up to 54.3 %. This is the highest for the plasma MHD generator.In fiscal 1999, behavior of flow field and plasma in the MHD generator was investigated and a lot of important data was accumulated. The data have suggested that a large positive swirl and a high Mach number were kept in the MHD generator and this led to the high isentropic efficiency. The present study has encouraged us to proceed to the next step in which an achievement of higher performances than the present ones is a main objective.