ABSTRACT

This tutorial session discusses a systematic approach to building a well balanced pipeline model. The presentation describes a step-by-step method for constructing a stable pipeline network simulation model. Explanation on local isolations, control conflicts, and pitfalls to avoid while building and setting up a good model, will also be explored. The audience is encouraged to participate in this dialogue as it pertains to gathering, distribution and transmission systems.

BUILDING MODELS

The purpose of this tutorial is to discuss some of the basic aspects of computer simulation of natural gas pipeline systems. It is written for the person who is familiar with the terminology and concepts of a pipeline, but who is new or in need of a refresher to modeling pipeline systems. First let's deline what pipeline simulation is. Pipeline simulation is the process whereby a computer model of a pipeline is used to simulate an actual pipeline system. The idea is to have the computer model duplicate or predict what is occurring in the actual pipeline system. The ability to predict what is going to happen with an actual pipeline system can be extremely useful in a number of ways. From an operational standpoint, pipeline simulation programs can be used to test operating changes on the model before implementing them on the actual pipeline system. Typical changes that can be tested with the model are variations in flow rates, pressures, temperature, gas quality, elevations, and compressor performance. You can also see what the effect of taking a line section out of service or turning off a compressor will be, by first trying it on the computer model. What it boils down to is that if you are unsure of something, you can experiment with the computer model of the pipeline system instead of the actual pipeline system itself. Another major use of pipeline simulation programs is in the desigu of pipeline systems. Pipeline simulation programs can be used to desigu a pipeline system from scratch or used to desigu an expansion to an existing system. While there are a few general rules you can follow when designing a pipeline system or expansion, there is still a lot of room for experimentation. Using a pipeline simulation program as an aid not only speeds up the desigu process, but also gives you more time to test different ideas and configurations, which in turn will usually result in a more efficient design. When you consider the high cost of buying and installing compressor units and pipe, even a small improvement in the design can yield considerable savings.

STEADY STATE SIMULATION

Steady state simulation is the process of simulating a pipeline system under steady state conditions, which simply means that the conditions are assumed to not change with time. Of course pipeline systems do not operate under perfectly steady conditions, but some pipeline systems do remain steady enough so that steady state simulation can be used to adequately model their behavior.

This content is only available via PDF.
You can access this article if you purchase or spend a download.