Wet Gas Flow Throttling Characteristics And Its Application In Flow Rate Metering

Wet gas is widespread in the process of gas production.Comparing with gas throttling,the throttling of wet gas is more complicated.Currently the prediction of pressure drop and the measurement of wet gas are very controversial.Correct prediction of wet gas throttling is significant for the design of gas well ground throttling and underground throttling.The pressure distribution of gas and wet gas in the Venturi tube,orifice and non-standard orifice were studied by the method of CFD and experiment.And the influence on the pressure drop by the throttling element,the gas phase flow and liquid phase flow in the wet gas was studied.Under the same gas phase flow,the pressure drop by the wet gas was greater than gas.At the throat the pressure was minimum and the flow rate was maximum.Under the same outlet pressure,the pressure loss of non-standard orifice plate is maximum,orifice takes the second place,the pressure loss of Venturi tube is minimum.The increase of gas phase flow and liquid phase flow in the wet gas will lead to the increase of differential pressure and pressure drop.Through comparing with the experimental data,the reliability of the numerical simulation is verified.The standard deviation distribution of the differential pressure signal collected in the experiment is relatively loose,and there is no monotonic relationship between it and x.However,with the increase of dry degree,the differential pressure signal has a tendency to decrease,and there is no obvious relationship between the working pressure and differential pressure signal.When the dry degree of x increases,the pressure loss fluctuation standard deviation decreases with the increasing of x,the curve tends to be slow,loss of pressure fluctuation standard deviation reduction is slow and with the increase of pressure,the pressure loss of signal fluctuation is bigger but this trend did not signal with pressure loss changes of dry degree so obvious,the error of the fitting curve is relatively large.A dry fitting degree and the differential pressure fluctuation equation,calculation formula with parameter fitting and Loma superficial gas coefficient calculation model,the derivation of a new flow.The venturi tube flow calculation model error is less than ±7.8%,the error of the orifice plate is less than ±9.5%,and the error of the non-standard orifice plate is less than ±11.7%.