This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Modeling of sub-sea outfall diffuser

 Hi all,

I have a task to model a storm water discharge pumping station, which transffers the stormwater to the sea via an submarine outfall diffuser. Well, I've included the scheme below, and I'd like to see  any suggestion, tip or trick on how to model this outfall diffuser in HAMMER V8.  I was thinking about the 'discharge to atmosphere' element, but the fact that it is acutally discharge to the sea is confusing. Also, the diffusers in this outfall (ref. to section y-y below) are open and they will allow bidirectional flow. The main purpose of this model shall be to analyze the transient events, so any advice in regard of transient behaviour of this setup is also very welcome.

Thanks in advance 



  • Hi Velibor,

    My initial thought is that this "diffuser" is really the connection to a known boundary hydraulic grade. The sea level would be the hydraulic grade at the diffuser, which the pump would be working against. So, you would simply model this as a reservoir with the elevation set to sea level and the invert set to the elevation of the diffuser. Reservoirs stay at a constant elevation during the transient simulation and can allow forward and reverse flow depending on the conditions. You could approximate the headlosses through the diffuser using a minor loss coefficient on the upstream pipe.




    Jesse Dringoli
    Technical Support Manager, OpenFlows
    Bentley Communities Site Administrator
    Bentley Systems, Inc.

  • Thanks Jesse,

    As usual your advice works just fine, the results are OK.