Study on gas–liquid two-phase flow and flow restriction and closure characteristics of hydrocyclone valve

Taking the hydrocyclone valve as the research object, the optimal physical model of the hydrocyclone valve is determined from the “S-type” flow restriction and closure. The numerical method was employed to study the gas–liquid two-phase under various inlet velocity (0.80, 1.05, and 1.25 m/s) conditions. The results showed that the “S-type” flow restriction and closure were not only related to the gas volume distribution of the hydrocyclone valve with its own stroke but also related to the water level of the collecting well where the hydrocyclone valve was installed. The interior of the hydrocyclone valve creates a low-pressure area with an eccentric circular cross section, and the low-pressure area extends to the downstream pipe. The low pressure flow field regions have a negative pressure area and a saturated steam pressure lower than that of water vapor, which indicate that bubble flow and cavitation flow occur simultaneously. After stable operation (the water level in the collection well is not rising), the inlet flow rates of 0.80 and 1.05 m/s occupy less space in the downstream pipeline than the inlet flow rate of 1.25 m/s, which is the optimal operating range.