This paper studies the gas-liquid flow splitting in T-junction with inclined lateral arm.The separation mechanism of the T-junction is related to the pressure distribution in the T-junction.It is shown that the separation efficiency strongly depends on the inclination angle,when the angle ranges from 0° to 30°,while not so strongly for angles in the range from 30° to 90°.Increasing the number of connecting tubes is helpful for the gas-liquid separation,and under the present test conditions,with four connecting tubes,a good separation performance can be achieved.Accordingly,a multi-tube Y-junction separator with four connecting tubes is designed for the experimental investigation.A good agreement between the simulated and measured data shows that there is an optimal split ratio to achieve the best performance for the multi-tube Y-junction separator.