高温环境下料浆大流量输送管流特性研究

为分析大流量管道输送过程中温度上升对料浆管流特征的影响，得出高温环境下料浆最佳输送管径及初始流速等参数，建立了充填料浆输送L管模型，基于流变试验获取料浆塑性黏度和屈服应力，利用COMSOL数值模拟软件分析了高温环境下不同温度、管径以及初始速度对应的管流速度场特性。结果表明：随着温度升高，充填料浆屈服应力以及塑性黏度随之降低；在弯管与水平管相接处，流态不稳定，料浆速度层出现较大变化，由塞流推进转化为速度自上而下递增的流动模式，易造成堵管、爆管；温度提高会导致中心最大流核区面积减小，温度为40、50、60 ℃时，最大流核区径向长度分别为0.09、0.07、0.05 m，减小率为22.2%，最大流速随之增加，当温度为40 ℃时，径向最大流速为2.978 m/s，温度增加至60 ℃，最大流速增大至3.135 m/s；随着管径增大，塞流最大流速区面积增加，管径为200 mm、240 mm时，最大流速区径向长度分别为0.1 m、0.12 m，最大流速随之减小，管径自200 mm增大至240 mm，最大流速由2.977 m/s变为2.876 m/s；随着进口速度增加，料浆中心最大流速区域增大，对塞流区域面积大小影响较小。基于上述试验成果，为减少输送阻力损失，提高矿山效益，建议矿山输送料浆参数选取温度40~50 ℃，管径200 mm，初始流速2.5 m/s。上述分析可为矿山充填设计及进一步研究管道输送流态问题提供一定的理论依据。

Flow Characteristics of Slurry Conveying Pipe with Large Flow under High Temperature Environment

In order to explore the influence of temperature rise on slurry pipe flow characteristics in the process of large-flow pipeline transportation，parameters such as optimal slurry pipe diameter and initial flow rate were obtained in the high-temperature environment，and the filling slurry transportation L-pipe model was established.Based on the rheological test，the plastic viscosity and yield stress of slurry were obtained.The velocity field characteristics of different temperature， pipe diameter and initial velocity in high temperature environment were analyzed by using COMSOL numerical simulation software.The results showed that the yield stress and plastic viscosity of the slurry decreased with the increase of temperature.At the junction of the bend pipe and the horizontal pipe， the flow pattern is not stable， and the slurry velocity layer changes greatly. The advance of the plug flow is transformed into the flow mode of increasing the speed from top to bottom， which is easy to cause pipe blockage and burst.When the temperature is 40 ℃， 50 ℃ and 60 ℃， the radial length of the maximum flow core is 0.09 m， 0.07 m and 0.05 m， respectively， with a decrease rate of 22.2% and a corresponding increase in the maximum flow velocity. When the temperature is 40 ℃， the maximum radial flow velocity is 2.978 m/s， the temperature is increased to 60 ℃ and the maximum flow velocity is increased to 3.135 m/s.When the pipe diameter is 200 mm and 240 mm， the radial length of the maximum flow zone is 0.1 m and 0.12 m， respectively. The maximum flow rate decreases accordingly. The pipe diameter increases from 200 mm to 240 mm， and the maximum flow rate changes from 2.977 m/s to 2.876 m/s.With the increase of inlet velocity， the area of maximum velocity of slurry center increases， which has little influence on the area of plug flow.Based on the experimental research， in order to reduce the loss of conveying resistance and improve the benefits of the mine， it is suggested to select the parameters of conveying slurry in the mine: temperature 40~50 ℃， pipe diameter 200 mm， and initial flow rate 2.5 m/s.The above analysis results can provide certain theoretical basis for the actual mine filling design and further study on the flow pattern of pipeline transportation.