摘要
目的研究在喷砂工艺过程中,喷嘴的收缩角、喉部半径及扩散角3种结构对出砂平均速度和出砂总量的影响规律及原因。方法利用EDEM-Fluent耦合模型,对喷砂喷嘴内气固两相的运动状态进行模拟,并通过实验验证其正确性。以喷嘴的不同结构大小设置正交表进行仿真实验,运用方差分析法(F检验),分析各因素水平出砂平均速度和出砂总量的变化规律,并利用控制变量法,进一步探究喉部半径对出砂平均速度和出砂总量的影响原因。结果由出砂平均速度方差分析可得,喉部半径的F值为3716.044,收缩角的F值为380.102,出砂平均速度随着喉部半径的增大而快速增大,随着收缩角的增大而减小。由出砂总量方差分析可得,喉部半径的F值为103.695,收缩角的F值为13.101,出砂总量随喉部半径的增大而快速减小,随着收缩角的增大而缓慢增大。当收缩角和扩散角不变的情况下,随着喉部半径增大,喷嘴内负压增大,导致气相流速增大,进而使出砂平均速度增大。随着喉部半径增大到8 mm时,出砂平均速度不再增大,且有略微下降,其峰值为184.65 m/s。在砂粒生成速率相同的情况下,得出喉部半径越大,砂粒速度越大,砂粒在喷嘴内的停留时间越短,收缩段待喷出的砂粒质量越少,且分布状态越稀疏。结论验证了EDEM-Fluent耦合模拟喷嘴内气固两相流场是合理可行的。基于这一仿真模型,得出了出砂平均速度及出砂总量分别与喷嘴不同结构参数之间的关系规律,其中喉部半径对两者的影响最为显著。随着喉部半径越大,出砂平均速度越大,单位时间内在喷嘴出口处统计到的砂粒总量越少。
This paper aims to study the influence rule and reason of the contraction angle,throat radius and diffusion angle of the nozzle on the average sand production speed and total sand production amount during the process of sandblasting.The EDEM-Fluent coupling model was used to simulate the gas-solid two-phase movement in the sandblasting nozzle,and the correctness of the model was verified by experiments.The simulation experiment was carried out by setting the orthogonal table with different structure sizes of nozzles.The analysis of variance method(F test)was used to analyze the variation rule of average sand production speed and total sand production amount at each factor level.The influence reason of throat radius on average sand production speed and total sand production amount was further explored by using the control variable method.From the variance analysis of the average sand production speed,the F value of throat radius to 3716.044 and the F value of contraction angle to 380.102,the average sand production speed increased rapidly with the increase of throat radius,but decreased with the increase of contraction angle;From the variance analysis of the total sand production amount,the F value of throat radius to 103.695 and the F value of contraction angle to 13.101,the total sand production amount decreased rapidly with the increase of throat radius,but increased slowly with the increase of contraction angle;When the contraction angle and diffusion angle were invariable,the negative pressure increased with the increase of throat radius,resulting in the increase of gas phase flow speed,and then the average sand production speed increased.When the throat radius increased to 8 mm,the average sand production speed no longer increased and slightly decreased,and its peak value was 184.65 m/s;In the case of the same sand generation rate,it is concluded that the larger the throat radius,the greater the sand speed,the shorter the residence time of the sand in the nozzle,and the less the mass of sand to be ejected from the contraction section and the more sparse the distribution state.It was verified that EDEM-Fluent coupling simulation of gas-solid two-phase flow field in nozzle was feasible and reasonable.Based on this simulation model,the relationship between average sand production speed and total sand production amount and different nozzle structural parameters was obtained,among which the throat radius had the most significant effect on the two.The larger the throat radius,the greater the average sand production speed,the less the total amount of sand counted at the nozzle outlet per unit time.
作者
周大鹏
马学东
杜昱霖
张凡
陈燕
王海令
ZHOU Da-peng;MA Xue-dong;DU Yu-lin;ZHANG Fan;CHEN Yan;WANG Hai-ling(School of Mechanical Engineering and Automation,University of Science and Technology,Anshan 114051,China;Anshan Changhe Metallurgical Equipment Manufacturing Co.Ltd.,Anshan 114031,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2022年第1期192-201,211,共11页
Surface Technology
基金
国家自然科学基金项目(51775258)
辽宁省自然科学基金重点项目(20170540458)
精密与特种加工教育部重点实验室基金(B201703)。
