Példafeladatok

Tutorial

1. The definition of the geometry and topology of the network for the staci program without the pumps in the network.
2. Series running with the previously given consumptions of the network, where in the place of the pump 10 different supply is applied (as negative consumption) from 0 to 2 x $Q_{nominal}$.
3. Draw the characteristic curve of the system from the 10 solutions (with given consumptions it is possible to draw it.)
4. Choose a pump for the flow rate $Q_{nominal}$, and the necessary system height, and place it into the system.
5. Rerun of the system with the previously given consumptions (100%), and with 10% (according to nights) and 190% (according to the peak time) consumptions.

6. Calculate the needed end reservoir (pool) area, so that the total water level in this reservoir stays in between 2-4 meters with the obtained daily water consumption.
7. Write a documentation about the solution in a detailed description of the above listed steps, with an attachment of a ‘spr’ staci project file which can be found on the server.

On the Staci web page click on ‘staci program indítása hálózatos módban’, then opening the Java application the network computing program will start. After accepting the terms the program can be started. (If it does not work adjust the Java security level to ‘medium’.)

Every user will receive a personal email with the login name and password.

A new project can be created with the program or one of the previously saved projects can be opened. (Attention! Every user can only see the projects saved under their own login name. We kindly ask everyone to save their projects under the name ‘group_serialnumber_versionnumber.spr’ – eg. ‘group_1_ver2.spr’, and at the end the documentation should contain the very last and final version number. )

Creating a hydraulic model involves the insertion of the elements, the connection of elements and defining their properties.
By inserting a new element a new pipe, pool, pump… etc. can be created. These are automatically created with the right number of nodes (at the beginning and end points).

Elements can be connected by clicking on the node – the marker of the node should change to a red rectangle - and pulling it to the node we want to connect it with. The nodes will be connected only if clicking on ‘Yes’ when the question ‘Are you sure to connect these edges?’ pops up. (The nodes will not be connected if they are only on each other!!!)

The properties of the created edges (denoted by a, b, c, and d) and nodes (denoted by p and r) also have to be defined. We can give the properties of an element by right clicking on it. The identifier (ID) of an element or node cannot be changed, but by the Label name we can refer to its name in our model. Moreover, here we can give the needed parameters such as diameter, length, roughness in the case of pipes (here negative λ has to be given!), water level and bottom level in the case of pools, performance curve in the case of pumps, etc.

We also have to define the nodes, their label, height and their consumption. (Attention! The picture of the model only shows the topology of the system, it does not contain the height above the sea level, it can only be given by the height of the nodes.)

For the calculations to be performed first the changes have to be saved! The parameters can be checked in the list of nods and elements.
(Remark: Even if one or more parameters are not given, the calculations will be carried out, since the program will run with the default values. Most of the times these differ from the parameters of the given problem, therefore it won’t give the expected results!)

By clicking on Calculations/Compute hydraulics the program will carry out the stationary computations on the hydraulic model defined by the given parameters. This takes a few seconds, we will notice when it is done.

With the program we can also carry out multiplications. At the end of our problem solving, with this we can check for example if the water level in our pools (with given areas) are valid.

After the calculations, the visualization of the results are possible, where the resulting values of pressure, velocity, etc. can be checked in graphical form.

In Project\Project properties we can get the list of all the iterations from the result file if we set the Debug level to 2.
In the Calculations menu point we can obtain the list of all the data (properties) of the nodes or elements, then the list can be copied to clipboard and pasted into, for example, an excel file, making the drawing of the performance curves easier. The data, of course, can be reloaded into the program.
We can also export the data. The exported file can be saved onto the computer as an .xml file, and from there can be reloaded into the program. (Attention! The final, and actual program version must be on the server! Saving the results to our own computer might be useful to look for mistakes.)

The data of the network elements

In the following examples:
z [$m$]: Height
f [$m^3/h$]: Consumption
H [$m$]: Bottom level
h [$m$]: Water level