船用燃气轮机网垫级进气滤清器二次夹带影响机理

The re-entrainment of droplets in the inlet filtration components of marine gas turbines severely affects the gas intake quality and the safe operation of gas turbines. To address this issue, the formation and influence mechanisms of droplet re-entrainment in the wire mesh filter were studied, and a comparative analysis was conducted on the effects of different inlet air velocities and droplet diameters on the liquid film thickness on the surface of the mesh and the mass of re-entrainment. The results show that incoming droplets tend to deposit upstream of the mesh segment and form a liquid film due to velocity gradients and inertia effects. Liquid film stripping is the main form of re-entrainment under marine operating conditions, occurring at a critical inlet air velocity between 4 and 4.5 m/s. The compact arrangement of adjacent wire mesh layers accelerates the airflow, and intensifies shear effect on the liquid film, which in turn increases the stripping film mass. This should be avoided during mesh fabrication. With the increase of the inlet air velocity, the overall thickness of the liquid film decreases, while the mass of stripping film increases. The increase in droplet diameter leads to easier blockage of the mesh pores and the local increase in film thickness, eventually leading to the overall decrease in film thickness but the increase in stripping film mass, which seriously affects the filtration efficiency. At a droplet diameter of 20 um, the filter fails.