  The cavitation flow of linear-polymer solutions around a cylinder is studied
by performing a large-scale molecular dynamics simulation. The addition of
polymer chains remarkably suppresses the cavitation. The polymers are stretched
into a linear shape near the cylinder and entrained in the vortex behind the
cylinder. As the polymers stretch, the elongational viscosity increases, which
suppresses the vortex formation. Furthermore, the polymers exhibit an entropic
elasticity owing to the stretching. This elastic energy increases the local
temperature, which inhibits the cavitation inception. These effects of polymers
result in the dramatic suppression of cavitation.
