Computed method for the thermal buckling performance of a constrained non-circular heated pipeline with an oval inverted arch

Abstract

This study focuses on the thermal buckling analysis of a confined noncircular pipeline with an oval inverted arch subjected to thermal loads. A trigonometric formula is employed to illustrate the radial inward deflection of the pipeline resulting from the rigid confinement of the surrounding medium (soils/rocks). The governing equations are derived by integrating the classical shell theory with energy criteria. These equations are solved to obtain the temperature–displacement equilibrium paths and critical temperature variations. Furthermore, a comprehensive comparison is conducted to validate the accuracy of the proposed computational method. This favourable alignment with other available solutions substantiates the effectiveness of this investigation. Finally, the impacts of varying central angles, ovalities, and thickness-to-radius ratios on the thermal stability of a noncircular pipeline with an oval inverted arch are analysed. These conclusions indicate that an increased central angle and ovality significantly affect the thermal stability of the system.