Flow-induced noise is closely related to the flow characteristics through an
adiabatic capillary tube and a transition pipe, most existing methods for
suppressing flow-induced noise are passive. An aerating technique is
proposed based on the pressure feedback in the transition pipe to actively
suppress flow-induced noise. Three-dimensional simulations of flashing are
presented by performing the Schnerr-Sauer cavitation model coupling with the
Mixture model. For the turbulence model, the large eddy simulation approach
is used. With the installation of aerating module, the pressure fluctuation
in the transition pipe is weakened significantly, and the phenomenon of
bubble collapse is suppressed. Numerical results illustrate that the
transient pressure of the monitoring points downstream of the capillary
outlet oscillates seriously due to the bubble bursting; the shedding process
of the bubble group is observed according to the vapor-liquid interface in
the transition pipe. In addition, the oscillations of monitored transient
pressure are suppressed with the application of aerating module. Then the
noise source can be partially reduced actively in essence. This paper is
devoted to understanding the two-phase flow characteristics of refrigerants
in a transition pipe and presents a practical method to suppress noise near
the capillary outlet.