Simulation and design improvement of a low noise control valve in autonomous underwater vehicles

Control valves are used to close off piping and prevent backflow. Radiated noise is generated when gas discharges through the check valves. In this study, three-dimensional numerical simulations were conducted to observe the flow patterns and to measure the flow fluctuations when the control value had different valve openings. The internal aerodynamic noise from the check valve was computed by using a frequency domain acoustic analogy, based on the Lighthill acoustic analogy. These results not only provided an understanding of the flow pattern in check values, but also were used to determine the location of the noise and the noise characteristics. The optimized water-microjets system, used for reducing the noise emitted by gas jets, was obtained by Max Kandula. The water-microjet were referenced and designed into the modified check value. The experimental results indicated that the modified value produces lower noise. (C) 2018 Elsevier Ltd. All rights reserved.