This paper studies the effects of internal fluid on the stability of
parametric vibration of a top-tensioned riser (TTR), where the effects
of internal flow on the parametric instability charts are analyzed.
Results show that both the internal flow density (mass per unit length)
and velocity exert an influence on the instability charts. The internal
flow density has more influence on the instability region. As the
internal flow density changes, both the shape and the position of the
instability charts will change.