Static and Dynamic Stability Analysis of Pipes Conveying Fluid with Different Boundary Conditions

In this paper, stability analysis of pipes conveying fluid is considered. The pipe structure is modelled using the Euler-Bernoulli beam theory and the fluid flow effect is taken into account as a distributed load along the pipe length which contains the inertia, Coriolis and centrifugal forces. In order to achieve different boundary conditions, both ends of the pipe are constrained with two lateral and two bending linear springs. The governing equation of the system is developed using the extended Hamilton’s principle and expressed in the matrix form by applying the method of separation of variables and the Galerkin technique. Then, via the standard eigenvalue analysis method the stability analysis of the system is done and effects of some parameters such as mass flow, gravity and the type of pipes’ boundary condition on the type of instability and the stability margin of the pipe conveying fluids are considered and some conclusions are drawn.