针对高压冷凝器中换热管与管板连接结构的密封可靠性问题，以TA2钛合金换热管分别与TC4、TA24钛合金管板组成的接头为研究对象，采用热-力耦合有限元仿真方法，模拟了自熔焊与坡口焊焊接过程的温度场、残余应力场。仿真结果与实验验证结果相近，证明了模型的准确性。结果表明，相同的材料规格（Φ16*1的TA2管与Φ40*150的TC4管板）下，自熔焊的残余应力峰值为738.5 MPa，优于坡口焊的753.8 MPa；相同的焊接形式（自融焊）下，采用Φ16*1的TA2管与Φ40*150的TC4、TA24两种管板，TC4板的残余应力为738.5 MPa，TA24为546MPa。

Focusing on the sealing reliability challenges of the connection structures between heat exchange tubes and tube sheets in high-pressure condensers, this study investigates the joints composed of TA2 titanium alloy tubes and TC4 or TA24 titanium alloy tube sheets, respectively. A thermal-structural coupled finite element simulation method was employed to model the temperature and residual stress fields during the autogenous welding and groove welding processes. The simulation results demonstrate a close agreement with experimental data, thereby verifying the reliability of the model. The results indicate that for the same material specifications (TA2 tubes of Φ16×1 mm and TC4 tube sheets of Φ40×150 mm), the residual stress peak is 738.5 MPa for autogenous welding, which is superior to the 753.8 MPa for groove welding. Under the same welding form (autogenous welding) with TA2 tubes (Φ16×1 mm) and TC4/TA24 tube sheets (Φ40×150 mm), the residual stress is 738.5 MPa for TC4 sheets and 546 MPa for TA24 sheets.