Pipe System Geometry Sample Clauses

Pipe System Geometry. The principal elements in the pipe system are constant diameter pipe sections which can contain fittings such as bends, valves and compressors as shown in Figure 1. The end points of pipe sections are called nodes and are classified either as junction nodes or fixed pressure nodes. These are depicted in Figure 2 and Figure 3. junction node - a node where two or more pipes meet or where flow is put into or removed from the system. If a pipe diameter change occurs at a component such as a valve or a compressor, this point is a junction node. fixed pressure nodes - a node in the system where the pressure is known. This is usually a connection to a storage tank or reservoir or a source or discharge point of specified pressure. Each system must have at least one fixed pressure node. A third geometric feature of pipe systems are primary loops which are described as follows: primary loop - a closed pipe circuit with no closed pipe circuits contained within it. If the junctions, primary loops, and fixed pressure nodes are identified as described above the following holds for all pipe systems: p = j + ℓ + f - l (1) where p = number of pipe sections j = number of junction nodes ℓ = number of primary loops f = number of fixed pressure nodes A proper identification of pipe sections, junction nodes, fixed pressure nodes and primary loops is helpful to assure a proper system description. Equation (1) may be verified and Figure 4 illustrates this procedure. Figure 4 Sample Pipe System Demonstrating p = j + ℓ + f - 1 p (number of pipe sections) = 12 j (number of junction nodes) = 7 ℓ (number of primary loops) = 4 f (number of fixed pressure nodes) = 2 A number of example pipe systems are described in schematics shown in the EXAMPLES section. These examples are used to illustrate various points throughout this manual. For each of these examples a numbering scheme is included showing the numbering of the pipe sections, junction nodes, and the labeling of the fixed pressure nodes. The pipe and node numbers and fixed pressure node labels are automatically assigned as the systems are developed graphically in the Pipe2000 environment.