Numerical simulation on the throttling process of high pressure natural gas with low liquid content

In the throttling process of high-pressure natural gas with low liquid content, the throttle valve is blocked easily, and chain well shutdown is aroused. In order to solve this problem, the three-dimensional model for the throttling process of high-pressure natural gas with low liquid content was established by using the software Fluent. Then, the effects of liquid plug length, liquid holdup and liquid viscosity on differential pressure and overpressure time of throttle valve were analyzed. It is shown that liquid plug length, liquid holdup and liquid viscosity all have a great influence on the gas-liquid two-phase flow field. The liquid plug which is formed during the throttling of high-pressure natural gas with low liquid content greatly hinders the movement of the gas phase, resulting in the rapid increase of the pressure difference between two ends of the throttle valve. The peak pressure difference increases exponentially with the increase of liquid plug length and liquid holdup, and linearly with the increase of liquid viscosity. And the overpressure time increases linearly with the increase of liquid plug length and liquid viscosity.