Context. Flows of plasma along a coronal loop caused by the pressure difference between loop footpoints are common in the solar corona. Aims. We aim to investigate the possibility of excitation of loop oscillations by an impulsively driven flow triggered by an enhanced pressure in one of the loop footpoints. Methods. We carry out 2.5D magnetohydrodynamic (MHD) simulations of a coronal loop with an impulsively driven flow and investigate the properties and evolution of the resulting oscillatory motion of the loop. Results. The action of the centrifugal force associated with plasma moving at high speeds along the curved axis of the loop is found to excite the fundamental harmonic of a vertically polarised kink mode. We analyse the dependence of the resulting oscillations on the speed and kinetic energy of the flow. Conclusions. We find that flows with realistic speeds of less than 100 km s~(?1)are sufficient to excite oscillations with observable amplitudes. We therefore propose plasma flows as a possible excitation mechanism for observed transverse loop oscillations.
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机译：上下文。在太阳日冕中，由环脚点之间的压力差引起的沿冠状环的等离子流很常见。目的我们旨在研究由回路脚位之一中的压力升高触发的脉冲驱动流激发回路振荡的可能性。方法。我们对具有脉冲驱动流的日冕环进行了2.5D磁流体动力学（MHD）模拟，并研究了环的振荡运动的性质和演化。结果。发现与等离子体沿着环路的弯曲轴高速移动相关的离心力的作用激发了垂直极化扭结模式的基波谐波。我们分析了所产生的振荡对流的速度和动能的依赖性。结论。我们发现，现实速度小于100 km s〜（？1）的流足以激发具有可观察幅度的振荡。因此，我们提出等离子体流作为观察到的横向环路振荡的一种可能的激发机制。
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