Neoclassical transport is studied for large helical device (LHD) configurations in which the magnetic axis has been shifted radially by determining the mono-energetic transport coefficient and the effective helical ripple. With respect to the transport in the long mean-free-path collisionality region—the so-called 1/ν transport—the optimum configuration is found when the magnetic axis has a major radius of 3.53 m, which is 0.22 m inward shifted from the `standard' configuration of LHD. In the optimized case, the effective helical ripple is very small, remaining below 2% inside (4/5) of the plasma radius. This indicates that a strong inward shift of the magnetic axis in the LHD can diminish the neoclassical transport to a level typical of so-called `advanced stellarators'.
大型螺旋装置（LHD）中，通过确定单能输运系数和有效螺旋波纹，研究了磁轴径向位移后的新经典输运。在长平均自由程碰撞区域——即所谓的1/ν输运——中，当磁轴大半径为3.53 m时，发现了最优配置，该位置比LHD的“标准”配置向内偏移0.22 m。在优化情况下，有效螺旋波纹非常小，在等离子体半径的4/5以内保持在2%以下。这表明，LHD中磁轴的强向内位移可以将新经典输运降低到典型所谓“先进仿星器”的水平。