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

User data extention - sum across all nodes

Hi,

I am working with the model of water network DMA in the city for the project of loss reduction.

I am trying to figure out if there is a way to have a formula en user data extention which will calculate the weighted average of the pressure for each node in a given timestep (weighted with the demand). 

So, the formula will be like: pressure*demand/(total demand of the model at this time step)

I am trying to find a way to calculate CASP (Current Average Sistem Pressure), which requires wieghting pressures for each node for each time step (on the base of how big is node's demand). 

So, is there is a way to use "total demand of the model" in the formula?

Or maybe it can be "sum of inlet flows" for the given time step?

Thanks in advance

Anna

Parents
  • Hello Anna,

    This would require a combination of formula based user data extensions.

    If running an EPS analysis, you can find the total flow demanded from your entire network in the Calculation Summary. However, you would have to note the total demands at each time-step manually. So if you have a one hour time-step for a duration of 24 hours then you would have to note the total demands for the entire 24 hours.

    Now, for the pressure component create a formula based UDX for the junction such as Demand * Pressure / Total Demand of the network at that time-step.

    Again this would be for only a single time-step. If you want for all the time-steps then you can copy the same formula for a number of time-steps using the values for the given time-step as found out earlier.

    Here is the article for creating formula based UDX for reference;

    Creating Formula-Based User Data Extensions

    See if this works.


    Regards,

    Yashodhan Joshi

  • Thanks, Yashodhan

    So, there is no way to use the total demand inside the formula?

    Because I am running EPS for a calibrated model of DMA for one week with 5-minutes timestep.

    I could export demand/pressure time-series for each node into excel and then do the analysis, but we are talking about 2000 time-steps for 430 nodes.

  • Hi Anna, currently formula-derived user data extensions (formula UDX) cannot perform functions on time-series. One option to consider is to use the Post calculation processor to calculate the statistic you're look for (which gets stored in another, non-formula UDX), and then create your formula UDX based on that. See more: Using the Post Calculation Processor for statistical analysis of results


    Regards,

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

Reply Children
No Data