【摘要】 高塔内壁防腐设备工作时需在火电厂高塔内做高速上下往复运动,这一过程产生的活塞风可能导致设备的振动,对喷涂质量有重要的影响。为了研究风速和设备运行速度对活塞风的影响,文章根据Bernoulli原理推导设备在不同运行状态下活塞风风速的计算公式;采用Fluent软件模拟设备高速运行下的流体速度场及压力场分布。研究表明:设备速度一定的前提下,顺风运行时产生的活塞风风速随设备运行速度和风速差值的增大而增大,逆风运行时产生的活塞风风速随着风速的增大而增大;由于设备逆风运行时活塞风效应显著,设备在上行和下行时应分别采取不同的速度曲线;在风速一定时,轿厢运行速度越快,活塞风风速越高;设备在启动后加速4s时顶、底面压差达到最大值129.39Pa,设备尾部气流速度峰值同样达到最大值11.33m/s;阻塞比越大,活塞风效应越显著,在满足结构设计的前提下,设备尺寸选用3m×3m×5m是合理的。研究结果为提高喷涂质量提供了一定的理论依据和数值参考。更多还原

【Abstract】 An anti-corrosion equipment used to protect the inside wall of tower moves up and down at high speed inside the tower of electric power plant.In this process,the generated piston wind,which potentially causes the vibration,has a significant influence on the quality of spraying.To study the impact of winds and operating speeds on piston wind,a formula,in accordance with Bernoulli principle,was derived to calculate the speed of piston wind under different operating conditions.Additionally,Fluent software was used to simulate the velocity field and pressure field of fluid while the equipment moved under high speed operation.The result shows that when the equipment speed is given,the speed of piston wind increases with the increasing of operating speed and the difference of wind speeds in the context of following wind.In another case of headwind,the speed of piston wind increases with the increasing of wind speed.Due to the significant piston effect against the wind,a different velocity curve should be adopted respectively for up-link or down-link.When the wind speed is given,the faster the car runs,the higher the speed of piston wind is.As a consequence,the pressure difference between the top and the bottom of the equipment reaches the maximum value of 129.39 Pa whenaccelerated in 4 s,as well as the peak value of airflow velocity reaches maximal 11.33 m/s in the tail.Furthermore,the significant degree of piston wind effect increases along with the increasing of blockage ratio.Hence,the size of 3 m×3 m×5 mis reasonable to meet the demand of structure.The proposed research can provide theoretical and numerical basis for improving the quality of spraying.更多还原