热流变形(BCF)变形喷嘴流场的研究

AIR-FLOW OF HOT FLUID TEXTURING (BCF) JET

本文利用二维多普勒激光测速仪对BCF技术最关键部位——BCF变形喷嘴的变形管射流场进行了全面测试,并利用片光源对射流场进行了观察,另外还利用间接的办法,对BCF变形管内流场进行了实验研究。实验研究表明,BCF变形管内流场是一特殊的亚音速管内流场,该流场具有较高的湍流度和速度梯度,速度分布紊乱,绕变形管轴线旋转较强烈,并以较高频率抖动等特点。

The hot fluid texturing process (BCF) is a new type of technology making a continuous filament yarn bulked in a hot fluid jet. The BCF process has been widely used because of its high production rates and improved bulk obtained from three-dimensional crimp. To understand the air-flow in BCF texturing tube, the laser Doppler anemometer has been used to investigate the characteristics of its el'flux. Other experiments and theory are used to analyse the air-flow in the tube. The flow is found to be subsonic, vibrational, strongly turbulant, and rotary.