Example
for EnergyPlus Line Diagram Generation[LINK]
A series of figures are provided below to detail the
process for generating an EnergyPlus line diagram.
1. Obtain a simple engineering line diagram for
the system. This system is a simple cooling system
that employs a primary/secondary pumping setup with a one-way
common pipe to circulate chilled water through a building. Figure
shows the simple line diagram for the system.
Simple line diagram for the
example system, (recreated from Reed and Davis
2007)
2. Identify all the loops in the
system. This system contains only one plant loop.
Loop name: Cooling Loop.
3. Identify the demand side and supply side of
the loop. The half loops are depicted in Figure.
Breakdown of a loop into its
constituent half-loops
4. Identify the components in the
system. While identifying the main components in the
loop, it should be noted that this loop has a
primary/secondary pumping setup, and that there is a common
pipe that allows for flow imbalance. (Note: The PlantLoop
object in EnergyPlus has a provision for the input of a common
pipe. The user only has to specify the existence of a common
pipe in the loop, and the program calculates its position in
the loop). The primary pump is shown below is shown in Figure.
A component in the
loop
5. Identify all the nodes in the
system. As mentioned above, placing a node on each
side of a component is a good way to pinpoint all the nodes in
the system. This process should be repeated for every
component in the loop. Figure shows the
placement of all the nodes on Individual components, while Figure shows all the nodes
in the system.
Node placement on
components
Nodes in the
system
Note: No nodes were placed on the common pipe, but its
existence should be specified in the PlantLoop
object.
6. Identify all the branches in the
system. Remember to add the bypass branches to the
operating components (except the pumps). Branches have to
start and end with nodes, and should contain at least one
component. The branches are denoted by the blue lines in Figure.
Branch definition
7. Identify the position of the connectors in
the system. The PlantLoop
accepts only one splitter-mixer pair per half loop. The
connectors are defined by using branches; a splitter can have
one inlet branch and any number of outlet branches whereas a
mixer can have any number of inlet branches and one outlet
branch. All the connectors in the loop are denoted by the
green lines in Figure.
Splitters and mixers in the
loop
8. An EnergyPlus diagram can be generated by using all
the identified components. The complete schematic is shown in
Figure.
Example for EnergyPlus Line Diagram Generation[LINK]
A series of figures are provided below to detail the process for generating an EnergyPlus line diagram.
1. Obtain a simple engineering line diagram for the system. This system is a simple cooling system that employs a primary/secondary pumping setup with a one-way common pipe to circulate chilled water through a building. Figure shows the simple line diagram for the system.
2. Identify all the loops in the system. This system contains only one plant loop. Loop name: Cooling Loop.
3. Identify the demand side and supply side of the loop. The half loops are depicted in Figure.
4. Identify the components in the system. While identifying the main components in the loop, it should be noted that this loop has a primary/secondary pumping setup, and that there is a common pipe that allows for flow imbalance. (Note: The PlantLoop object in EnergyPlus has a provision for the input of a common pipe. The user only has to specify the existence of a common pipe in the loop, and the program calculates its position in the loop). The primary pump is shown below is shown in Figure.
5. Identify all the nodes in the system. As mentioned above, placing a node on each side of a component is a good way to pinpoint all the nodes in the system. This process should be repeated for every component in the loop. Figure shows the placement of all the nodes on Individual components, while Figure shows all the nodes in the system.
Note: No nodes were placed on the common pipe, but its existence should be specified in the PlantLoop object.
6. Identify all the branches in the system. Remember to add the bypass branches to the operating components (except the pumps). Branches have to start and end with nodes, and should contain at least one component. The branches are denoted by the blue lines in Figure.
7. Identify the position of the connectors in the system. The PlantLoop accepts only one splitter-mixer pair per half loop. The connectors are defined by using branches; a splitter can have one inlet branch and any number of outlet branches whereas a mixer can have any number of inlet branches and one outlet branch. All the connectors in the loop are denoted by the green lines in Figure.
8. An EnergyPlus diagram can be generated by using all the identified components. The complete schematic is shown in Figure.
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This documentation is made available under the EnergyPlus Open Source License v1.0.