Just to clarify about surge tank filling way?
is waterhammer consider that the tank is always full!!
regards
Hello Bushra,
Are you modeling one way or two way surge tank?
In case of one-way surge tank with the check valve at the entrance, there is no any inflow in the tank under normal conditions, and closed under normal i.e. non-transient conditions and open when the HGL drops below water surface elevation of tank.
Whereas a two-way surge tank allows both inflow and outflow like normal tanks. Hammer assumes that surge tanks are filled after transient event has happened.
Here is technote about surge tank, for your reference.
Modeling Reference - Surge Tanks
Regards,
Sushma Choure
Bentley Technical Suppport