Investigation On The Characteristics Of Gas-liquid Slug Dissipation In Combined Pipe

We can eliminate the impact of liquid slugs to the separator by changing the expanding diameter ratio and downward inclination angle of the inlet pipeline of GLCC.This paper mainly analyzed the characteristics of gas-liquid slug flow along the inlet pipeline of GLCC by numerical simulation and experiment.This paper developed a method of simulating slug flow by the user-defined function and a one-dimentional steady-state model of slug flow.We simulated the slug dissipation using this method and the simualtion results show that this method is feasible.It can be seen that the enlargement of declination angle ? and diameter ratio K are helpful to the improvement of slug dissipation and the diameter ratio K is more effective.In the case of a larger spiral diameter D(physical truth)the dissipation laws show the same characteristics as the straight inclined pipes.The liquid holdup fluctuation curve is smoother for the sprial pipe in the same condition.Due to the effect of centrifugal force,the gas-liquid interface is inclined and it is very helpful for the separation in the cyclone part.The characteristics of gas-liquid slug flow along the inlet pipe are researched in the experiment.Because of the impact of the vertical pipe the pressure in the inlet of declinational pipe is different from the inlet of horizontal pipe.It is found that liquid slugs will grow in the vertical pipe and the slug length will get the maximum in the top of the veitical pipe.And the slug velocity will decrease in the vertical pipe and get its minimum value in the top of the veitical pipe.In the declined pipe we can regard the increase of liquid slug velocity and the decrease of liquid length as a linear relationship.Compared with the fully developed condition,the liquid film is thinner and the liquid slugs are irregular in the declinational pipe,as the development of the slug flow the liquid slug area and liquid membrane area will be brought back.The impact of geometric construction(declination angle ?,diameter ratio K,location of the enlargement hole)to the effect of slug dissipation is researched.It is found that diameter ratio K is the most important parameter to the effect of slug dissipation.The areas that are easy for liquid slugs to dissipate are located in the upper left and lower right corner of slug flow region.The increase of declination angle ? is helpful for the slug dissipation and as the increase of declination angle the slug velocity will increase in the declination pipe.In the condition of a larger declination angle(-21°~-40°)the impact of declination angle to the slug dissipation can be ignored.In the range of-21°~-40°as the increase of declination angle the the gas-liquid interface tend to be more smooth.The location of the enlargement hole to the slug dissipation can be ignored.