Thanks Azam for your reply.
Can this simple system modelled in sewergems??'
Moreover, I am not sure which dictate the full or partial flow in a pipe like the above system. One thing I Believe that if the hgl is above the pipe then it will be always full flow under pessure pipe.
Now I don't know whether the system to be inlet controlled or outlet controlled. In the first case, it (discharge ) will be governed by orifice flow but if it is outlet controlled many things will come in to play, like pipe length, friction factor, slope and governed by darcy weishbach/manning equn. Am I right?
But I don't know how to know whether it is inlet or outlet flow.
Please show me some light.