Simulation Settings

When using the simulation and cost calculations method, once you have defined the probability of failure and the maintenance scenarios for the failure mode, you can then define the simulation settings and run the simulation. To do this, click Simulate in the Task Manager.

The Simulate window will appear, allowing you to specify the settings used in simulation.

Note: The Simulate window is also used to specify simulation settings in order to predict system availability and operation costs at the system level in the FMRA. In this case, it is accessed by selecting the system that you want to simulate and choosing FMRA > Calculations > Simulate (Availability).

The software uses the simulation engines from ReliaSoft’s BlockSim software for system reliability, maintainability and availability analysis.

• Simulation Setup

• Operation Time: Specify the amount of operating time to be simulated (i.e., the simulation time) and the time units. The value you enter here will change the system's operating time, shown in the item properties.

• Number of Simulations: Enter the number of simulations that will be performed. A higher number of simulations will take longer to process but may yield more accurate results.

• Repeatability

• Use Starting Seed: If you need your results to be repeatable, select this option and enter a seed, which specifies a starting point from which the random numbers used in simulation will be generated. The same random numbers and, therefore, the same simulation results will be generated when the same seed value is used.

• Number of Threads: You can run simulations in multiple threads, which may improve performance and save time when simulating complex configurations. In general, using twice as many threads as the number of cores in your computer is appropriate; a ratio of threads to cores greater than this 2:1 ratio is likely to degrade performance. To have the application automatically determine the number of cores in your system and set the number of threads accordingly, click the Suggested button beside the Number of Threads field.
  
  The number of threads you use affects repeatability of results. In order for your results to be repeatable, you must use the same number of threads and the same seed each time you simulate the diagram. When you are using multithreading, the seed that you specify is the seed for the first thread; seeds for additional threads are sequential (e.g., if you are using 3 threads and your starting seed is 7, the threads will use 7, 8 and 9 as the starting points for random number generation).

• Comparative Options: (FMRA only) New in Version 2020, you can specify task types to exclude from the FMRA simulation, allowing you to create results for a certain set of conditions. For example, you might exclude all preventive tasks to get a sense of how a corrective-only maintenance strategy differs from one incorporating preventive maintenance. To exclude task types, simply select the relevant check box(es) in the Comparative Options area. You can exclude all corrective tasks, inspection tasks (not including the inspection portion of on condition tasks), preventive tasks and/or on condition tasks. If any task type is selected for exclusion, an orange light will be displayed in the Simulation Results Status column in the FMRA after simulation.

Click OK to perform the simulation.