Solar-type young stellar objects undergo periodic, energetic outbursts that appear to be the result of enhanced mass accretion driven by the gravitational instability of their disks. Such FU Orionis outbursts may have profound consequences for the earliest solids in a protoplanetary disk, namely the refractory inclusions containing abundant calcium and aluminum (CAIs). We present models of the orbital evolution of centimeter-radius particles representing large CAIs in marginally gravitationally unstable disks. The hydrodynamical evolution of the disks is calculated with a fully three-dimensional code, including compressional heating and cooling in the beta cooling approximation. The particles are initially distributed uniformly throughout the disk, which extends from 1 to 10 au around a solar-mass protostar, but within ∼100 yr the particles are concentrated by gas drag into regions surrounding the spiral arms and rings formed by the gas disk. The particles settle down toward the disk midplane, only to be lofted repeatedly upward by shock fronts. Large-scale radial transport both outward and inward occurs, with significant numbers of particles reaching the outer disk (∼10 au) and surviving for considerably longer times than would be the case in a quiescent disk with gas pressure monotonically decreasing with distance from the protostar. Individual particles experience wide ranges of disk temperatures during their journeys, ranging from 60 K in the outer disk to nearly 2000 K in spiral features. Future work will consider the implications for CAI rims of the thermochemical processing experienced during FU Orionis outbursts.

太阳型的年轻恒星会经历周期性的、高能的爆发，这似乎是由它们的圆盘的引力不稳定性驱动的质量吸积增强的结果。这种 FU Orionis 爆发可能对原行星盘中最早的固体产生深远的影响，即含有丰富的钙和铝 (CAI) 的耐火包裹体。我们提出了厘米半径粒子的轨道演化模型，这些粒子代表边缘重力不稳定的圆盘中的大型 CAIs。圆盘的流体动力学演化是用完整的三维代码计算的，包括 β 冷却近似中的压缩加热和冷却。这些粒子最初均匀地分布在整个圆盘中，围绕太阳质量的原恒星从 1 到 10 au，但在大约 100 年内，粒子被气体拖拽集中到由气体盘形成的螺旋臂和环周围的区域中。粒子朝着圆盘中平面沉降，只是被激波前沿反复向上抬高。发生向外和向内的大规模径向传输，大量粒子到达外盘（~10 au）并存活的时间比静止盘中的情况要长得多，其中气压随着与原恒星的距离而单调递减. 单个粒子在其旅行过程中会经历广泛的圆盘温度，范围从外圆盘的 60 K 到螺旋特征的近 2000 K。未来的工作将考虑在 FU Orionis 爆发期间经历的热化学处理对 CAI 边缘的影响。