直叶片液力减速器内部流场及空化性能研究  

Internal Flows and Cavitation Performance of a Hydraulic Retarder Equipped with Straight Blades

作　　者：康灿[1] 张贵峰[1] 李利婷 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《机械设计与制造》2016年第11期92-96,共5页Machinery Design & Manufacture

基　　金：江苏高校优势学科建设工程资助项目(苏政办发[2014]37号)

摘　　要：提出一种新型的可调工况直叶片液力减速器,设计两种工况调节板位置,进而采用三维非定常数值模拟和Rayleigh-Plesset空化模型,对减速器运行全过程中的内部流场和力矩性能进行模拟与分析,并重点讨论了减速器内的空化现象。研究表明:(1)整个减速器的制动过程中,力矩系数基本保持恒定,工况调节板位置越靠近叶轮时的力矩系数越小。空化现象并未对减速器的制动力矩构成显著影响。(2)离心力造成的低压和高转速均是导致空化产生的关键因素。工况调节板越靠近叶轮,空化现象越严重。(3)在相同转速条件下,工况调节板距叶轮的轴向距离越大,其所受轴向合力也越大;轴向合力值随转速的增加而增大,方向始终指向叶轮。A novel hydraulic retarder equipped with a condition adjusting plate and straight blades is propos Two axial positions of the plate are devised. Three-dimensional flows inside the hydraulic retarder are simulated and the torque performance of the hydraulic retarder is analyzed accordingly. The whole simulation is carried out based upon a practical operation process featured by transient variations of rotational speed~ of special interest is the cavitation phenomenon which is treated with the Rayleigh-Plesset cavitation model. The results show that the torque coefficient remains nearly constant in the whole operation process. And the torque coefficient is relatively small as the condition adjusting plate is near the impeller. Nevertheless, the torque coefficient is not significantly affected by cavitation. Both centrifugal force and low pressure at vortex core play an important role in facilitating cavitation inceptior And cavitation turns to be severe as the axial distance between the plate and impeller is redueed~ As rotational speed keeps invariaut, the axial hydraulic force exerted upon the condition adjusting plate increases with the distance between the plate and impeller. Meanwhile, the hydraulic force magnitude rises with rotational speed But the force direction remains pointing towards the impeller.

关 键 词：液力减速器 工况调节板 空化 瞬态过程 流场 力矩系数 

分 类 号：TH13[机械工程—机械制造及自动化] TH12