供热直埋热水管道弯管的整体与局部应力分析

Integral and Local Stress Analysis of Bend Pipe in Direct Buried Hot Water Heating Pipelines

摘要: 城镇供热直埋热水管道局部元件如弯头和三通等受力复杂，采用ANSYS进行建模可以得到详细的应力状态分析。大型管道系统线路长，架空管道和埋地管道混合在一起，建立全尺寸的ANSYS模型不具有可操作性。START管道应力分析软件采用一维梁模型经典管道应力分析模型理论，在大型管道系统长管段模拟上优势明显。为验证其可靠性，本文对比了START软件与ANSYS软件对供热直埋热水管道弯头应力分析的结果，分析了弯头一次以及二次应力随管道内压、埋深、壁厚、曲率半径、转角的变化规律。对比结果表明，START软件在直埋热管管道弯头应力分析上可以得到与ANSYS一致的结果，并且建模方便、计算迅速，可为直埋供热管道弯头的整体与局部应力分析提供帮助。

Abstract: Local components of the directly buried hot-water heating pipelines, such as bends and tee joints, bear complex stress which can be obtained by detailed stress state analysis using ANSYS simulation. However, it is not operable to establish detailed full-scale ANSYS models for large-scale piping systems which combine long overhead pipelines and buried pipelines. START Pipe Stress Analysis Software, which is based on one-dimensional beam model for classical pipe stress analysis, has obvious advantages for pipe stress analysis on large-scale piping systems with long pipelines. To verify the feasibility of START model, we conducted stress analysis of bend pipe indirectly buried hot-water heating pipeline by using START model and ANSYS model, respectively. The influences of the internal pressure, buried depth, pipe wall thickness, radius of curvature and angle of the bend on the primary stress and the secondary stress of the elbow were analyzed. The simulation results show that the START model obtains consistent results with the ANSYS model in the stress analysis of bend pipes. The START model, which is characterized by convenience for modeling and high computational efficiency, can provide help for integral and local stress analysis of bend pipe in direct buried hot water heating pipelines.