垃圾气力输送过程中垃圾在弯管段的运动特性

Characteristic Analysis of Garbage Movement in Bend during Pneumatic Transmission

通过建立内径为0.5 m的弯管模型,模拟垃圾在管道的流动状态,研究垃圾的运动特性。结果表明:垃圾经过弯管后的速度变化量随着垃圾在弯管段入口速度的增大而线性减小,弯管段的附加垃圾压损随着气体速度与垃圾在弯管入口速度的相对速度的平方的增大而线性递减。利用此线性规律计算垃圾经过弯管的速度变化量和附加垃圾压损,并与仿真结果对比,速度变化量最大误差为8.18%,附加垃圾压损最大误差为9.25%。对相邻弯管间的最小直管段长度进行分析,结果表明弯管间最小直管段长度与系统提供的总压裕量和靠后弯管入口处垃圾速度有关,且管路是否堵塞的根本要素为系统提供的总压裕量和管道入口处的垃圾速度。

The flow of garbage in a pipe was simulated to study its kinematic characteristics by establishing a pipe bending model with inner diameter of 0.5 meters. The result showed that garbage velocity variation after it went through the bend decreased linearly with the increase of garbage velocity at bend inlet,and additional garbage pressure loss decreased linearly with the increase of square of relative velocity between air velocity and garbage velocity at bend inlet. Compared the garbage velocity variation and additional garbage pressure loss calculated by linear law with the ones calculated by simulation method,the maximum error of garbage velocity variation was 8.18%,and the error of additional garbage pressure loss was 9.25% at most. The minimum straight pipe length between adjacent bend was analyzed,which indicated that the minimum straight pipe length was related to margin of total pressure and garbage velocity at later bend inlet. And they were also the main factor which determined if the pipe net was blocked.