预浸带铺放过程温度场动态仿真与实验研究

Dynamic finite element simulation and experimental study on heat transfer in prepreg placement process

为了测量铺放过程中粘合点温度峰值和复合材料的温度场分布，构建了基于LabVIEW的温度场在线测量系统。实验中预浸带铺放5层，热风枪稳定温度为200℃。实验结果表明，随着铺放过程的进行，每一层预浸带的温度曲线都出现多个峰值，且峰值逐渐降低，其中第1个峰值即为粘合点温度，平均分别为80．1、91．4、101．3、113、108．3℃。由比较可知，各层预浸带粘合点温度逐渐升高。同时，建立了预浸带铺放温度场有限元模型，利用ANSYS中的生死单元以及循环加载技术，模拟了预浸带动态铺放过程。有限元模拟结果中的粘合点温度分别为71．8、96．2、104．3、107．9、105．3℃，与实验结果相比，误差可控制在10％以内，且粘合点温度越高，其准确性越好。

A temperature online measurement system based on LabVIEW was established, aiming at measuring the temperature peak at the nip-point and the temperature distribution in the prepreg placement process. In the experiment, 5 layers of prepreg were laid-up and the stable temperature of hot air was 200 ℃. The experimental results show that along with the placement process, the temperature curves of every layer have several peaks decreasing gradually and the first peak was the nip-point temperature. The nip- point temperatures of each layer increased gradually, they were 80.1 ℃, 91.4 ℃, 101.3 ℃, 113 ℃ and 108.3 ℃ respectively. In addition, a finite element model of temperature field was established and a dynamic finite element simulation for prepreg placement process was done by using the birth-death element strategy and the cyclic loading strategy in ANSYS. The nip-point temperatures in the finite element simulation results were 71.8 ℃, 96.2 ℃, 104.3 ℃, 107.9 ℃ and 105.3 ℃ respectively. The error of the nip- point temperature between finite element simulation results and experimental results can be controlled within 10%, and the higher the nip-point temperature get, the more accurate the result became.