modelling pump-sump using VOF
 

hello,
i am using vof method to model standard pump model ( v c patel et al. 1998). water flows from inlet into the sump and then through suction pipe. i have defined a fixed volume of air over water domain. for turbulence i am using ke-std with scalable wall functions. after convergence i found that streamlines form the water surface are entering into air domain!! (note: single phase results for same problem were fairly accurate)
please help me with suggestions and comments.