SewerGEMS Modeling a Transition Manhole (Force Main to Gravity Sewer)

Question

Hello , 
 I was looking for feedback on the tools available in SewerGEMS to model a transition manhole. (solver options, physical elements to include, etc..) 
 My objective is to model as explicit as possible the transition between pressure - gravity flows, including the effect of energy dissipater in the transition manhole, assess the culvert entrance capacity (inlet control). 
 Thanks in advance for your help, 
 Dennis Lopez

MPachlhofer · Accepted Answer

To model a transition manhole you can use one of two elements: manhole or a transition. This wiki explains the differences in connections for a manhole vs. a transition vs. a pressure junction. In this case it may not matter much which element that is used, but if the element connecting the gravity main to the force main has a depth to it beyond the depth of the connecting pipes I would recommend using a manhole. 
 The energy dissipater could be modeled in 1 of 2 ways depending on what you think more appropriately represents the element. It could be modeled using a headloss at the node element (manhole or transition) using the absolute headloss method or it could be modeled as a start control structure on the conduit. To model it as a start control structure on a conduit set the property labeled "Has Start Control Structure?" to 'True' and choose the control structure (depth vs. flow curve, weir, orifice, or functional) that best models the structure.