Unscheduled Time Steps and Their Impact on Modeling Flows (April 2023)

GoldSim is a powerful tool for dynamic simulation, designed to model complex systems that evolve over time. One of the key differences between GoldSim and Excel is that GoldSim carries out calculations at discrete intervals, known as timesteps.

During each timestep, GoldSim calculates the values of variables in the model, with many of these being a function of their previous values at the end of the previous timestep. This process is referred to as an update of the model. Although the term timestep actually refers to an interval of time, it is often used interchangeably with the term update (indicating a calculation at a point in time).

There are two kinds of updates in GoldSim: scheduled and unscheduled updates. Scheduled updates are directly specified prior to running the model, allowing you to tell GoldSim when you want these updates to occur.

In contrast, unscheduled updates are timesteps that are dynamically inserted by GoldSim during the simulation in response to changes in the system. These changes may include events that occur between scheduled updates, such as reaching an Upper or Lower Bound in a Pool or Reservoir. Unscheduled updates are included by default, but can be disabled if needed.

It is important to understand unscheduled updates, as they can affect the accuracy of flow outputs in the model. If you assume that flow outputs are constant over a scheduled update, you may make invalid assumptions about the behavior of the system.

In this webinar, we will discuss the importance of unscheduled updates and why they should generally not be disabled. We will also explain how to properly interpret and use flow outputs in the model. Lastly, we will explore under what circumstances it may be appropriate to disable unscheduled updates.

By understanding the role of timesteps and updates in GoldSim, you can create more accurate and reliable simulations of complex systems.

Below is a video recording of the webinar presentation:

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