2219铝合金板电子束焊接过程热流传输行为的数值分析（英文）

发布时间：2018-04-01 22:06

本文选题：热传递　切入点：流体流动　出处：《Transactions of Nonferrous Metals Society of China》2017年06期

【摘要】：提出一种基于有限体积法的二维数学模型,以研究20 mm厚2219铝合金板在电子束焊接过程的热传递、流体流动以及匙孔的动力学行为。采用一种能够实时跟踪匙孔深度的自适应热源模型来数值模拟电子束的加热过程。由表面张力、热毛细力、反冲压力、流体静压力以及热浮力等诱导的不同涡旋的热和质量输运作用与匙孔演变相互耦合。详细分析了一系列物理现象,包括电子束焊接过程中的匙孔钻取、塌陷、重新打开、准稳态过程、回填过程以及在此过程中的温度变化。结果表明,深度方向降低的电子束热流能减慢反冲压力的匙孔钻取速度,并促进准稳定状态的出现。在准稳定状态出现之前,匙孔会发生塌陷并加剧涡旋流体输运的复杂性。最后,所有的计算结果与实验结果进行对比,来验证数学模型的可行性。
[Abstract]:A two-dimensional mathematical model based on finite volume method is proposed to study the heat transfer, fluid flow and dynamic behavior of keyhole in the electron beam welding process of 2219 aluminum alloy plate with a thickness of 20 mm.An adaptive heat source model, which can track the depth of keyhole in real time, is used to simulate the heating process of electron beam numerically.The thermal and mass transport of different vortices induced by surface tension, thermocapillary force, recoil pressure, hydrostatic pressure and thermal buoyancy are coupled with the evolution of the keyhole.A series of physical phenomena are analyzed in detail, including keyhole drilling, collapse, reopening, quasi steady state process, backfill process and temperature change during electron beam welding.The results show that the heat flux of electron beam with lower depth can slow down the keyhole drilling speed of recoil pressure and promote the appearance of quasi-stable state.Before the quasi-stable state occurs, the keyhole collapses and increases the complexity of vortex fluid transport.Finally, all the calculated results are compared with the experimental results to verify the feasibility of the mathematical model.
【作者单位】：哈尔滨工业大学先进焊接与连接国家重点实验室;
【分类号】：TG456.3

【参考文献】