螺旋槽上游泵送机械密封端面间液膜压力脉动特性

为分析上游泵送机械密封微间隙内流场的动静干扰作用和压力脉动特性,以螺旋槽非接触式机械密封为例,运用滑移网格技术,对内部流场进行了多工况非定常数值模拟.分别计算了稳态和瞬态的模型内部压力速度分布,以及不同转速下的压力脉动时域变化和频谱特性,并与试验结果进行对比分析.研究结果表明:所用模拟方法可对内流场非定常特性进行较好描述,由于动静干涉的影响,各转速下机械密封流场内压力脉动呈明显的周期性变化规律;压力脉动是非定常流动现象的重要特征,主要受槽频和轴频的影响.

Pressure fluctuation characteristic of mechanical face sealing clearance of spiral groove in upstream pumping

To analyze the interaction of the rotating and static parts and the pressure fluctuation of micro clearance flow field in the upstream pumping mechanical seal, unsteady simulation was conducted to calculate the flow field on multiple working conditions based on the sliding mesh technique. The distribution of velocity and pressure inside the model at steady and unsteady states were studied. The time domain and frequency spectrum characteristics of the pressure fluctuation at different rotating speeds were also revealed. The simulation results were compared with the experimental results. Results show that internal flow field was displayed in detail through the simulation method and pressure pulsation at different speeds changes periodically because of the influence of rotating-static coupling. The pressure fluctuation,as a very important characteristic of the unsteady flow, is affected by the groove frequency and the shaft frequency.