换热管缺陷扭转模态导波检测的仿真研究

摘要

换热管作为换热器的关键部件之一，对其进行检测至关重要。扭转模态T（0，1）超声导波具有无频散特性，在换热管检测中有广阔的应用前景。采用ANSYS 有限元方法对T（0，1）模态导波检测进行仿真研究，为克服在ANSYS中Solid 164单元无旋转自由度而无法加载转角或扭矩的问题，提出了通过施加刚体转动间接激励T（0，1）模态导波的方法。研究了转角加载和扭矩加载两种不同激励方式，仿真结果表明两种激励方式都可以成功激励出T（0，1）模态导波，缺陷定位准确，且扭转模态导波在弯管中衰减更大。%It is important to inspect heat exchanger tubes,which are key components of a heat exchanger. Recently,the guided wave of T(0,1 )mode is used to realizing a long range inspection of heat exchanger tubes due to its advantage of non-dispersion.The inspection process of torsional guided waves is simula-ted in ANSYS software using finite element method.A new method to generate the T(0,1 )mode guided wave in the finite element model is present.One end of the tube is set as a rigid body.By applying an an-gle or torque on the rigid body,guided waves of T(0,1 )mode can be generated.Moreover,the propaga-tion of the T(0,1 )mode guided wave in a curved pipe is analyzed based on the above model.Simulation results show that defects are located accurately although the T(0,1 )mode guided wave has a greater at-tenuation in the curved pipe.