This study devolped two physical models to represent two annular silicon rod distribution patterns in 42 pairs of furnaces: a three-ring layout and a four-ring layout. It investigated the impact of different silicon rod radii and distributions on flow field, temperature field, and energy consumption in Siemens polycrystalline silicon furnaces, to reduce the high energy during polysilicon production. It was revaled that the energy consumption increases with the radius of the silicon rod under two layouts, and this change is jointly affected by the flow field and temperature field inside the furnace. Additionally, it was observed that radiation energy consumption concerning the inner-ring silicon rod within the reduction furnace exhibited an initial increase followed by a subsequent decrease as the silicon rod radius grew. In contrast, the radiation energy consumption of the outer-ring silicon rod displayed a positive correlation with the silicon rod's radius. These findings led to the proposal of an energy consumption reduction strategy for large Siemens reduction furnaces, advocating the adoption of a three-ring layout to minimize overall energy consumption in polycrystalline silicon reduction furnaces effectively.