Magnetohydrodynamic (MHD) instabilities allow energy to be released from stressed magnetic fields, commonly modelled in cylindrical flux tubes linking parallel planes, but, more recently, also in curved arcades containing flux tubes with both footpoints in the same photospheric plane. Uncurved cylindrical flux tubes containing multiple individual threads have been shown to be capable of sustaining an MHD avalanche, whereby a single unstable thread can destabilise many. We examine the properties of multi-threaded coronal loops, wherein each thread is created by photospheric driving in a realistic, curved coronal arcade structure (with both footpoints of each thread in the same plane). We use three-dimensional MHD simulations to study the evolution of single- and multi-threaded coronal loops, which become unstable and reconnect, while varying the driving velocity of individual threads. Experiments containing a single thread destabilise in a manner indicative of an ideal MHD instability and consistent with previous examples in the literature. The introduction of additional threads modifies this picture, with aspects of the model geometry and relative driving speeds of individual threads affecting the ability of any thread to destabilise others. In both single- and multi-threaded cases, continuous driving of the remnants of disrupted threads produces secondary, aperiodic bursts of energetic release.

磁流体动力学 (MHD) 不稳定性允许从应力磁场中释放能量，通常在连接平行平面的圆柱形通量管中建模，但最近，也在包含两个脚点在同一光球平面内的通量管的弯曲拱廊中。包含多个单独螺纹的未弯曲圆柱形通量管已被证明能够承受 MHD 雪崩，因此单个不稳定的螺纹可以使许多螺纹不稳定。我们检查了多线程冠状环的属性，其中每个线程都是通过光球驱动在逼真的弯曲冠状拱廊结构中创建的（每个线程的两个脚点在同一平面上）。我们使用三维 MHD 模拟来研究单线程和多线程冠状环的演变，这些冠状环变得不稳定并重新连接，同时改变各个线程的驱动速度。包含单线程的实验以表明理想 MHD 不稳定性的方式不稳定，并且与文献中的先前示例一致。额外线程的引入修改了这张图片，模型几何和各个线程的相对驱动速度影响了任何线程破坏其他线程的能力。在单线程和多线程情况下，连续驱动中断线程的残余物会产生二次的、非周期性的能量释放爆发。模型几何形状和单个螺纹的相对驱动速度会影响任何螺纹破坏其他螺纹的能力。在单线程和多线程情况下，连续驱动中断线程的残余物会产生二次的、非周期性的能量释放爆发。模型几何形状和单个螺纹的相对驱动速度会影响任何螺纹破坏其他螺纹的能力。在单线程和多线程情况下，连续驱动中断线程的残余物会产生二次的、非周期性的能量释放爆发。