基于二维叉排管束模型的刷式密封旋涡分离点分析  

Investigation into brush seal vortex separation point based on 2D staggered tube bundle model

作　　者：谭永发 刘美红[1] 康宇驰 王学良[1] 刘晋宾 

机构地区：[1]昆明理工大学机电工程学院,云南昆明650500

出　　处：《排灌机械工程学报》2017年第7期602-608,共7页Journal of Drainage and Irrigation Machinery Engineering

基　　金：云南省科技计划项目(2012FB130);昆明理工大学分析测试基金资助项目(2016M20152203034)

摘　　要：为了进一步研究刷丝束内部气体流动,建立了刷丝束截面的二维紧凑叉排管束模型,运用Fluent软件对其进行气体流动数值模拟.首先根据网格独立性的判别标准,分析了网格加密程度对刷式密封数值模拟结果的影响,并以气流速度、压降和气体质量泄漏率的相对变化率作为网格独立性检验的参考量,得到独立于计算精度的大致网格数.其次,模拟分析了不同排距管束模型在各压差下的气体流动,得到分离点S与刷丝间距和上下游压差之间的关系.计算结果表明:网格数在400 000左右时对数值模拟结果误差在2%以下,网格独立.分离点S位置在经历前1~2排刷丝束时逐渐向下游移动,最后趋于稳定.随着刷丝间距和上下游压差的增大,分离点S均会沿着刷丝表面发生后移,且位置在高压差条件下相对变化不大.In order to study the internal gas flow in bristles in detail, a 2D staggered tube bundle mo- del for the cross section of bristle pack was established and the flow through the bundle was simulated using Fluent. According to the criteria of grid independency, namely the relative changes in flow rate, pressure drop and gas leakage rate, effects of mesh refinement degree on the numerical results, and an approximate number of mesh cells at which the computational results had been independent of mesh size were studied. Then, the gas flows were simulated at different pressure drops for different row spa- cing control bundle models, and the relationship of separation point position S with the gap of bristles and pressure difference across the bundle was obtained. It was shown that the relative changes in flow rate, pressure drop and gas leakage rate are all less than 2% when the number of grid is about 400 000. The separation point position S moves gradually downstream through the bristle rows 1 -2, and finally tends to be stable. With enlarging brush spacing and increasing pressure difference across the bundle, the position S moves downstream along the surface of bristle, and it keeps nearly unchanged at a higher pressure difference.

关 键 词：刷式密封 叉排管束 计算流体力学 网格独立性 分离点 

分 类 号：S277.9[农业科学—农业水土工程] TB42[农业科学—农业工程]