翅片安装高度对共转盘腔减阻特性影响的数值研究

Numerical Investigation on Effects of Installation Height of Fins on Drag Reduction Performance of Co-rotating Cavity

关键词:  翅片  共转盘腔  数值模拟  旋流比  总压损失

Key words:  Fins  Co-rotating cavity  Numerical simulation  Swirl ratio  Total pressure loss

摘要:

为了探索翅片安装高度变化对共转盘腔径向内流总压损失的影响规律，对不同转速、翅片径向安装高度下的去旋系统展开了数值研究，得到了不同工况下径向内流共转盘腔的流场结构及总压损失分布曲线。研究结果表明：翅片安装高度能够影响盘腔内部旋流比分布情况，翅片吸力面流体的旋流比大于压力面侧；随着翅片安装高度的升高，减涡器的总压损失先减小后增大；在所研究工况及结构参数下，翅片下端径向高度与盘腔高度比值为0.476时减涡器的减阻效果最好，压力损失系数降低16%左右；在一定条件下，翅片式减涡器总压损失主要集中在翅片所在盘腔分区；翅片上端和下端盘腔分区总压损失对减阻性能的影响起决定性作用，且上端的影响大于下端的影响。

Abstract:

To research the effects of the height change of the fins installation on the total pres-sure loss in inflow of co-rotating cavity, numerical simulation was carried out to cal-culate the gas in de-swirl system with varied installation heights under different rota-tional speeds. The flow structures and the diagrams of total pressure loss under varied condition were obtained. The results show that the installation height of fins can af-fect the distribution of swirl ratio in the disc cavity. The flow rate of the fluid in the suction surfaces of the fins is greater than that of the pressure surfaces. And as the height of the installation of the fins increase, the total pressure loss of the vortex re-ducer tends to decrease at first and secondarily increase. Under the studied conditions and structural parameters, the drag reduction effect of the vortex reducer is the best when the ratio of the radial height of the lower end of the finned to the height of the disk cavity is 0.476. And the pressure loss coefficient is reduced by about 16%. Under certain conditions, the total pressure loss of finned vortex reducer is mainly concen-trated in the disk cavity area where the finned is located. The total pressure loss at the upper and lower end of the fin cavity exert a decisive part in the influence of drag re-duction performance, and the influence of the upper end is greater than that of the lower end.