Manhole Headloss

Hamid,

Is there more to this question about why you are asking? I'm asking because this question seems a little strange without more details.

Mark

Thanks Mark for your attention.
As you know "Manhole drop" and "Manhole headloss" are challenging issues.
Sometimes designers don't spend time for the "Manhole headloss" and just assume 0.05 to 0.10m "Manhole drop" to come up with "Manhole headloss".
I wanted to ask :
1-how can I see calculated headloss in the felxTable
2-If headloass is a big number like 0.15m, how software comes up with "Manhole drop".

Thanks

Hamid

Hamid,

In future posts it would probably help if your question included more details like this because others would be able to better understand the question that you're asking rather than trying to assume an interpretation and taking their best guess. It would also help others that may have a similar question find answers to their questions more quickly and in the end it will help whomever decides to answer to provide you with a more succinct answer because they understand that question, which should save everyone some time.

Mark

Hamid,

In reference to your second question are you referring to how the software comes up with the manhole drop when you are using the default design constraints (Components > Default Design Constraints) for designing a system with the GVF Rational (StormCAD) or GVF-Convex (SewerCAD) solvers? or Are you referring to something else?

Also, it looks like Jesse answered your first question and if you had any additional question about how to input the information for headloss into another node Scott covered that.
 
Regards,
Mark

Yes I am going to use GVF-Convex (SewerCAD) with default design constraints

Hamid,

The "headloss" result field that you can add to your flextable (and view in the properties) shows the hydraulic friction/minor loss through the structure as a result of the selected structure loss method. This is the loss from the upstream to the downstream side of the structure. With a drop structure, there may also be a drop in hydraulic grade from the upstream conduit to the structure itself, from water basically spilling into the structure.

To answer the questions posed:

1) hydraulic friction/structure loss is reported in the flextables in the "headloss" field. You can click the yellow edit button to add it if it's not already visible.

2) Can you provide some clarification here on what you mean by the software "coming up with" the "manhole drop"? In general, the "drop" in the context of automated design constraints is the distance from the upstream pipe's downstream invert (where it connects to the drop structure) and the invert of the structure itself. The hydraulic grade is independent of this. If the structure loss through the manhole causes the HGL on the upstream side to rise above the invert of the incoming pipe, the backwater analysis will effect the HGL of the upstream conduit accordingly. If this doesn't answer your question, some additional clarification would help.

Hamid,

The "headloss" result field that you can add to your flextable (and view in the properties) shows the hydraulic friction/minor loss through the structure as a result of the selected structure loss method. This is the loss from the upstream to the downstream side of the structure. With a drop structure, there may also be a drop in hydraulic grade from the upstream conduit to the structure itself, from water basically spilling into the structure.

To answer the questions posed:

1) hydraulic friction/structure loss is reported in the flextables in the "headloss" field. You can click the yellow edit button to add it if it's not already visible.

2) Can you provide some clarification here on what you mean by the software "coming up with" the "manhole drop"? In general, the "drop" in the context of automated design constraints is the distance from the upstream pipe's downstream invert (where it connects to the drop structure) and the invert of the structure itself. The hydraulic grade is independent of this. If the structure loss through the manhole causes the HGL on the upstream side to rise above the invert of the incoming pipe, the backwater analysis will effect the HGL of the upstream conduit accordingly. If this doesn't answer your question, some additional clarification would help.