Hydraulic modelling software that can handle zero pressure

[WASH in the city]

Hi team,

I have the challenging task of commissioning a hydraulic model of a city water network that has sustained heavy damage on top of long term neglect. The context means that, for various reasons including non or semi-functioning pump stations, damaged pipes, etc., the network is not always pressurised in all sectors.

I have worked with InfoWorks some time ago, but my memory of the detailed functionality is rusty. It is my understanding that most conventional modelling software struggles with occurrences of zero pressure in the network. I have heard that perhaps Piccolo and EPANET-PDX may be software packages that can handle instances of zero pressure. Firstly, is this correct? And secondly, what about other packages? Can sophisticated software such as Bentley WaterGEMS handle zero pressure instances?

Many thanks for your advice!

 

[hydrae]

WASH

While they can model zero and negative pressures, they are no longer accurate, so the default is to give an error. When the pressure drops below the vapor pressure of water at the operating temperature the properties of vapor are very different. Hazen-W equations no longer apply and the coefficients on Darcy-W are very different which exceeds the design of the modeling software.

Hydrae