Study on new superconducting magnet structure for fusion device applying high specific heat of supercritical helium

超临界氦高比热聚变装置新型超导磁体结构研究

基本信息

批准号：
13680573
负责人：
NISHIMURA Arata
金额：
$ 1.79万
依托单位：
National Institute for Fusion Science
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

项目摘要

The new structure of a cable-in-conduit superconductor applying supercritical helium with high specific heat was proposed and the usability and the potential were discussed. The following results were obtained.(1) Since the supercritical helium has a large heat capacity, it is possible to reduce the temperature rise at one over several tens using the supercritical helium when the AC losses or hearing by eddy current occurs.(2) When the circulation of helium gas is formed, the helium pressure does not keep constant at the critical pressure, for the pressure drop is caused by the flow friction. Therefore, the static supercritical helium must be applied as a heat capacitor. (3) For the constant heat generation such as nuclear heating, the independent helium circuit from the heat capacitor must be prepared to remove the continuous heating and to prevent from temperature rise. The independent circulation is able to be designed considering the heat generation density.(4) The current saturation in a stand by imbalanced current sharing, which is local heat generation, affects on the stability of the coil remarkably. The heat generation occurs during the coil excitation with about 100 seconds and is a quasi-steady heat load.(5) The stability test was able to be carried out in the critical helium under the heat load by flux-flow resistance and the situation of the strand current saturation.(6) The heat capacity of the supercritical helium to the flux-flow resistance was investigated and it was clarified that the capacity was improved over one order of magnitude than of pressurized helium.(7) The higher capacity is obtained in liquid helium, for the latent heat at boiling is available. However, the cooling ability will be reduced by the bubbles surrounding the conductor. So, the supercritical helium which does not have phase transition will be profitable.

提出了一个具有高特异性热量的超临界氦气的型电缆超导体的新结构，并讨论了可用性和电势。（1）由于超临界氦气具有较大的热容量，因此，使用超临界氦气在几个数十几个时降低温度升高，当会发生AC损失或听力时发生涡流电流。（2）形成氦气循环时，氦气压力在临界压力下并不能在压力下降，因为压力下降是由流量流失造成的。因此，必须将静态超临界氦作为热电容器应用。（3）对于恒定的热量产生（例如核加热），必须准备从热电容器中的独立氦回路去除连续加热并防止温度升高。考虑到热量产生密度，可以设计独立的循环。（4）通过不平衡的电流共享（即局部热量产生）在架子上的当前饱和度会显着影响线圈的稳定性。热产生发生在线圈激发期间，大约100秒钟，是一种准稳态的热负荷。（5）稳定性测试能够通过通量抗磁力的阻力在热量下的关键氦气中进行，并且链电流电流饱和的状况。（6）在量度上均高于速度的速度和量度的高度均匀的速度被调查了，并且澄清的是澄清的。（7）在液氦中获得更高的容量，因为可以使用沸腾的潜热。但是，导体周围的气泡将降低冷却能力。因此，没有相转换的超临界氦气将是有利可图的。