摘要
基于粒子图像测速(PIV)技术,测量了闭合循环脉冲XeF(C-A)蓝绿准分子激光器增益区的流场。研究了放电区域内流场中心区、近激光窗口区和过渡区在未放电条件下定常流场的流速特征及放电后不同时刻的流场形态,分析了放电后流场的恢复时间与风机转动频率、放电电压的关系。结果表明:在近窗口区域,存在流速缓慢的涡流;在流场中心区,流速较大且分布均匀;放电后瞬态出现了流速极慢的流场停滞现象。
Particle image velocimetry(PIV) technique is used to measure the flow field in the gain zone of a closed loop pulsed XeF(C-A) blue-green excimer laser. The flow velocity characteristics of the steady flow field in the center of the flow field, near the laser window and between the two parts in the discharge zone are studied. The flow field states in different time during the process of the discharge are analyzed. Furthermore, the relationships between the recovery time after discharge and the fan rotation frequency or the discharge voltage are discussed. The results show that there exit vortexes with slow flow velocity near the laser window. While in the center of the gain zone, the field is even with fast flow velocity. And in the moment after discharge, the flow field stagnation phenomenon with extremely slow velocity occurs.
引文
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