中国古代扇车类型考察与性能研究

A Study on the Types and Performance of the Winnower in Ancient China

西汉晚期以来中国传统扇车演化出开放式、半敞式和封闭式三大类型。应用计算流体力学软件进行数值模拟,综合比较各类扇车的技术水平。开放式扇车不能有效集中气流;半敞式扇车可以集中部分气流,但内部流场状况不佳;封闭式扇车采用轴部进风,内部流场逐步改善,发展出近代类型。对扇车的理解受到过水轮的启发,并有所超越。

Since late Han Dynasty, the traditional winnower in ancient China had developed into three types： the open, the half-opened and the closed. The flow field was simulated by the software of computational fluid dynamics （CFD）, the comprehensive comparison of technology level was done on winnowers. For the open winnower, the flow could not be focused effectively. For the half-open winnower, some flow could be focused, but the flow field was not well. For dosed winnower, the flow was guided from the axis, whose field had been optimized gradually. Thereafter, the modern winnower was developed from the last type, and the knowledge of winnower was inspired from the water wheel, even surpassing it.