Dynamic characteristics and responses of flow-conveying flexible pipe under consideration of axially-varying tension

As oil and gas industry is developing towards deeper ocean area, the length flexibility of pipes become larger, which may induce larger-amplitude displacement flexible pipe response due to lower structural stiffness against environmental operational loads. Moreover, these also convey internal flow. In other words, dynamic characteristics flow-conveying face great challenge, such as bucking flutter. this study, a pipe, under flow and, particularly, axially-varying tension, are examined through our FEM numerical simulations. First, governing equations models with tension developed. Then characteristics, including coupled frequency modal shape, presented. At last, corresponding stability behaviors discussed compared cases uniform tension. Our results show that quite different from And, time-spatial evolution exhibits profound wave propagation effect, e.g. peak value/position significantly change along mechanism based on WKB solutions. •The dynamics studied using stimulations. •Due non-uniform critical velocity wavelength gets smaller amplitude larger. •In displacement, found amplified. •As increases, first position third moves down.