When it comes to performing the design of water distribution networks, you will agree with us that one of the most complicated tasks, or one that requires more work on our part, is the calculation of water demands.
With Aqueducts we have tried precisely to facilitate tasks like this, incorporating into it options that allow the user to worry less about this type of task and concentrate more on the specific design of the water network.
In this video, we will show you which options are available for defining the average water demand of the nodes in the distribution network you want to design with our software.
Let’s get started.
When you have already performed, externally to the program, the calculation of the demands of the nodes of your network, the option you have is to select each node in your project and, through the corresponding properties dialog, enter the value in the Demand field.
Of course, if you are importing the water network from a Microsoft Excel file, as we have seen in a previous video, you have the option of also importing the water network nodal demands. Of course, it is understood that there is a column with the necessary information in the imported file.
This manual alternative, so to speak, is perhaps advisable in small or simple distribution networks in relation to water demands allocation.
But in many cases, even for the most basic ones, you will see that the options we have already included in the PARCELS tab in our CLOACAS and WATER DEMANDS ALLOCATOR software and, now, in AQUEDUCTS are the best option to keep the model updated.
When you get to this tab you will see that there are several panels, and the Parcels and Polygons panels contain the objects or tools that will allow you to perform an accurate modeling of the distribution of demands in the area you are studying.
When we speak about a Demand Parcel, think simply about a point in the drawing area that has information about the water consumption of a typical parcel or building in your project.
For example, suppose I want to represent the water demand per parcel of a single-family house of 450 square meters of extension in my project.
What I do is click the Edit button in the Parcels Panel and from this dialog I create it.
I assign a name and description.
I search among the available Water Demands Libraries for those containing water consumptions related to the land use of this typical parcel.
Note that here, by default, there are several types: residential, educational, etcetera.
Within the selected library, I choose and assign the use relative to the specific characteristics of our typical parcel. In this case, the total extension is the characteristic.
And, finally, I assign the quantity. In this case, one.
You will see that the total water demand of this typical demand parcel is updated here.
I close, saving the changes and, when returning to the drawing, I will see that this typical parcel is now available in the project’s demand parcels list.
What remains then is to start adding this demand parcel in the corresponding locations according to the urban project of the studied area.
These symbols can be resized as you see now.
In addition, to facilitate the manual creation process, you can select one or more parcels, right-click on the mouse, and select Copy to generate new parcels in the drawing area.
Assume that I have already added all the required parcels—which obviously is not true here, but the idea is to show you the potentiality of this tool. What remains to be done is click on this button to let the software perform the allocation of demand parcels to nodes and pipes.
You will see that a summary table is shown, informing you about the result of the allocation as well as the total water demand calculated.
Depending on the water demands allocation method you have chosen, here in the general settings, you will have the demand result in nodes.
For example, here the method of the average distribution is selected.
Therefore, you will see that the demand calculation for each node goes through two stages:
The first one is to determine which parcels are supplied for each pipe section in order to calculate the pipeline’s own water demand, which you can review in the properties of the section.
The second stage allows for determining the node’s demand. That demand of each pipeline connected to the node is divided by two and added to determine what the corresponding nodal demand is, such as here in the summary table of the node.
If you have done this work manually at some time, you will surely appreciate the importance of this addition to our software.
A very common situation is when the information regarding the type or classification of the terrain parcels in urban projects is annotated, in the corresponding plans, with a symbol or letter.
That is why we have included the option to read objects such as texts, circles, or points, grouped within a layer in a drawing file that can then be imported and converted to Demand Parcels.
Also, if there are polygons grouped in a layer, it is possible to associate them with the demand polygons that you have previously created in the project.
To show this we go to the import dialog of DWG or DXF files on the Drawing tab.
I select a file that contains, in the layer “Single Family Type 1,” the texts that indicate the front of each of these parcels.
Here it is mandatory that you have previously created at least a demand parcel so that you can associate it to imported objects by selecting it from this list.
When clicking OK and closing the message, you will see that the texts have been converted into demand parcels. Even easier, as you see.
It is also possible, in case the parcel’s data is presented as a point’s coordinate in a Microsoft Excel file, to perform the import and conversion into demand parcels.
The procedure is simple:
Let’s load the EXCEL files import dialog from the drawing tab.
Select the Excel file and the table or sheet with the information.
We must be sure to select the project’s demand parcel to which the locations to be imported will be assigned.
And finally, let’s select the columns in the source file with the necessary coordinates in order to know their location after the import.
In this case, I will not perform the import because the file I selected does not correspond to this project but, in any case, the procedure is clear.
Regarding the demand polygons, the calculation with them in your aqueduct projects is also quite intuitive, there being no difference from the general concepts used in the design of drinking water distribution networks and sewage collection systems.
When you click the Edit button in the Polygons Panel, PARCELS tab, you will see that the creation dialog offers you the options to create, edit, and delete demand polygons of the project, allowing you to enter, when creating a new one, a name and description.
You will also see that you have three types of polygons to be used in your projects.
The “Population density” polygon is the most used because it represents the relationship between the water demand and the population density that is usually defined in the urban development plans of the communities.
In this case, you must enter the density value and inhabitants per hectare, as well as the per capita water consumption to be used in the demand calculation of the polygons created from it.
The unitary flow polygons are those that allow you to estimate the demand from the product between the polygon’s respective area and a unitary flow that you specify here in this text box.
Finally, the tributary area or influence polygons are those that you would use to define tributary areas for nodes in order to be able to group within them parcels of demand. Thus the software can, by means of the sum of the grouped parcel’s respective water demands, determine the total demand associated with the polygon.
In this case, we will create one of density, with the following values.
I’ll save and close the dialog, to see that now this polygon is presented in the list of available ones in the project.
We are going to add one to the project, around here in the north of the area.
Again, assuming that we have all the necessary polygons to define the water consumption, it just remains for us to click the button to perform the automatic allocation.
The summary table shows, in addition to the information of the Demand Parcels, that it is related to the existing demand polygons.
Additionally, note that the polygon has been assigned to the pipeline closest to its centroid.
If I go to the pipe’s property dialog, I’ll see it listed in the report of parcels and polygons allocated.
Of course, the demand for node seven is also updated, as we see here, since the flow rate of one of the pipes connected to it has changed.
A particularity that the demand parcels and demand polygons have, which will serve you to analyze demand scenarios, is that if you go to the layers manager of the drawing and hide one of these elements, when performing again the demands allocation and calculation, you will note that this group of demands does not make part of the total demand, just like it does not exist in the project.
As you can imagine, the options to analyze design periods and water demand growth in your projects are multiple with this characteristic.
To conclude with the water demand allocation and calculation topic, we tell you that in the PARCELS tab you will also find two buttons that will allow you to export the information of demand Parcels and Polygons to an XML file that can be read by our software for the design of sanitary sewer networks, CLOACAS.
Likewise, it is possible to import a file with the information generated from that software into Aqueducts.
In this way we maintain consistency between what you do in both software when you design both systems, water supply and collection. At the same time, it is clear that this feature greatly reduces the work of creating and editing demand parcels and polygons in each project.
For instance, for this project we already have a file exported from CLOACAS, where the sewage collection network of the sector was designed. We want to include into aqueducts the information of demand parcels used in that project to carry out the corresponding design of the potable water distribution network.
So I click the import button.
Select the file and click Open.
In a few seconds, I see the different typical parcels for this urbanism have been created.
If I make the water demand allocation, we also see that the calculation is carried out without any inconvenience.
We then have the network ready with the information of average water demands assigned to the nodes automatically.
Most significantly is that any modification you make to the geometry of the network will not require you to edit demands or modify values. Just click the assign demands button and everything will be recalculated automatically.
Pretty useful for your designs, right?
Until the next video.