瓶颈开口角对二维颗粒流密度的影响

Effect of opening-angle θ at choke point on the density of granular flow on the two-dimensional conveyor belt.

此前曾研究过传送带出口处瓶颈开口角度对颗粒流的影响.在稀疏流状态下改变瓶颈开口角度θ,当θ大于15°时,颗粒流量Q随着cosθ呈线性变化,颗粒流量Q可表示为:Q(θ,v,R,ρ)=0ρ.R.v-K(ρ,R,v).cosθ(0ρ是开口角为90度时颗粒在瓶颈开口处的平均密度).本文着重研究了颗粒流量Q与速度v、瓶颈开口R以及颗粒密度ρ的关系,结果发现在稀疏流状态下颗粒流量Q在任何开口角度下与速度v以及瓶颈开口R都呈线性关系,但颗粒流密度ρ却是瓶颈开口角度θ以及开口尺寸R的函数,(ρR)与cosθ呈非线性关系.

The relationship between the granular flow rate Q of the dilute granular flow and the opening-angle θ at choke point on a two-dimensional conveyor belt was investigated. The result showed that the granular flow rate Q decreases linearly with the cosθ when the opening-angle θis larger than 15°. The expression of the flow rate Q can be written as： Q（θ,v,R,ρ）=ρo · R · v-K（ρ,R,v） · cos θ（ρois the density of the granule when the opening-angle θ equals 90 degree）. The result showed that the density of granular flow is dependent on the opening-angle θ and the exit width R. There is a nonlinear relation between the density of granular flow ρ（R） and the cosθ. The flow rate Q of dilute granular flow can be written as： Q（θ,v,R,ρ）=ρo · R · v-ρ（R） · R · v · cos θ.