Tips & Tricks: Manipulating and Splitting Sections in a Pipe Network
There are many situations in which we will end up using pipe segments of varying complexities in a Symmetry case. From short process piping to a single long transmission line or complex networks such as a gathering system or a flare header. The pipe segment in Symmetry is designed to contain a fair degree of detail such as fittings or detailed heat transfer with insulation that changes from segment to segment. With all of these varying degrees of detail and applications, we are often faced with making modifications to the topology of the piping system. This article highlights some of the functionality built into Symmetry to manipulate and split sections of a pipe.
The functionality described below is applicable to any type in any Symmetry workspace. The images used in this article are taken from the example SSDyn-OilGatheringNetworkAndBattery.vsym which can be found by going to the File menu and going to the Gathering and Distribution Networks section from the Applications Examples tool.
Figure 1. Pipe network used in the example
To get started open the pipe P-40_40_188 which is found in the Flowsheet SteadyState.PipeNtwrkSS. The elevation profile is found in the Pipe Detail tab as shown in Figure 2. This is where we can modify most details related to the sections of the pipe such as diameters, fittings or elevation.
Figure 2. Pipe Detail tab displaying elevation profile
Filter Elevation Profile
The first functionality we will discuss is the “Filter Current Elev Profile…” button. This feature allows us to reduce the number of sections in the pipe by using an algorithm behind the scenes to try to minimize the loss of accuracy. Reducing the number of sections is a simple technique to improve performance which may provide a meaningful boost in speed for dynamics systems or large pipe networks. When we click the button, we get a window where we can fine-tune the filtering to a desired compromise of speed versus accuracy. The accuracy can be significantly reduced in networks with steep elevation changes handling multiphase fluids at low velocities.
Figure 3. Filter elevation profile window
The filter elevation profile provides a variable to “request” a number of sections and behind the scenes it will provide a number of sections as close as possible to this value while preserving the accuracy as best as possible. It is important to note that filtering the current elevation profile of a pipe segment is an action that cannot be undone. In this example, we can see that a value of 12 results in 8 sections. To accept the filtered profile just click on Update Profile. The filtered profile is shown below in Figure 4.
Figure 4. Filtered elevation profile
Moving and Deleting Sections
Next we will explore the Move Section(s) and Delete Section(s) buttons. These buttons are very useful when we have fittings, or we configured specific details per section such as different diameters or heat loss parameters.
Figure 5. Move and Delete Section(s) buttons in the Pipe Detail profile
These buttons will display a dialog window where we can specify the modifications to be done on the pipe. The controls in this window are referenced by section numbers. If the pipe had fittings, then these labels will include them for easier referencing. For this example, we will move sections 3 to 5 to the end of the pipe after section 8 as shown in Figure 6.
Figure 6. Move sections dialog window
The pipe network will resolve as soon as this change is made. When making multiple changes it is recommended to first put the solver on hold. The pipe profile after the changes is shown in Figure 7.
Figure 7. Elevation profile after moving sections
Splitting a Pipe
The last feature to discuss is the button called “Split Pipe…” which is used to split a pipe into two separate pipes. The main purpose of this functionality is to enable us to connect more pipes somewhere in the middle of the line via a node, mixer or splitter. This button is found at the bottom of the pipe window, so it is visible regardless of the active Tab.
Figure 8. Split Pipe dialog window
Figure 9. PFD after splitting a pipe
Figure 8 shows the selection drop down box for splitting a pipe. The sections include the cumulative length in their labels for easier reference. After clicking split, the pipe will be automatically broken into two separate items in the PFD and reconnected. The flowsheet will try to solve if not on hold. We could now connect another pipe at this location.
In this article, we covered some basic functionality available in Symmetry to manipulate sections in a pipe. These features are quite valuable across workspaces, particularly when the different sections are configured to include specific details such as fittings, different diameters or heat loss settings.
Please contact your local support office if you have any questions or feedback on this or any other functionality in Symmetry.
Raul Cota, Ph.D, P.Eng., VMG Calgary