高温射流冲击大丝束碳纤维实验与仿真分析

Experimental and simulation analysis of high-temperature jet spreading of large size carbon fiber tow

为更好地研究大丝束碳纤维在射流冲击作用下的展纤机理,设计了高温射流冲击试验装置。通过正交试验,并引入极差这一指正参数,参数化地分析了热气流喷距、纤维丝束跨距和纤维丝束张力对展纤效果的影响。建立高温射流流场的三维CFD模型,通过实验与仿真对比分析射流中心轴线上的速度分布来验证仿真模型的正确性,获得流场中心平面上的速度分布云图,并对高温射流冲击作用下纤维壁面的压力和温度的分布情况进行分析。CFD仿真和射流冲击试验的结果较好地吻合,通过分析结果得出适合于48K大丝束碳纤维展纤的最优工艺参数。当在喷距为80 mm,纤维跨度为100 mm,砝码质量为15 g条件下进行展宽,纤维铺展均匀,展宽效果最佳,宽度可达到50 mm。

In order to study the fiber spreading mechanism of large carbon fiber tow under jet impact,a high-temperature jet spreader is designed.Through the orthogonal experiments,the effects of hot-air spray distance,the tow span and the tow tension on the fiber-forming effect have been analyzed quantitatively by introducing the motion of range analysis.By building the 3-D CFD model of the high-temperature jet spreader,the simulation model is verified by comparing the velocity distribution on the central axis of the jet through experiment and simulation.Moreover,the velocity distribution on the center plan of the jet flow is obtained,and the distributions of the pressure and the temperature of the fiber wall under the jet impact are analyzed.The experiment results are in great agreement with those bye simulation.By analyzing these results,the optimized process parameters for 48K carbon fiber tow is obtained.Under the condition of the spray distance is 80 mm,the fiber span of 100 mm,and the weight of 15 g.The final spreading thickness of the large size fiber tow is more evenly,and the final width of the fiber tow is up to 50 mm.