Simulation in BlockSim

[Klaus Denkmayr]

Can anyone from ReliaSoft explain what exactly are inner and outer loops in the BlockSim simulation module?
I couldn't find it in the manual.

Please, no mathematical definition - I am used to Monte Carlo methods.

Thanks.
Klaus

[RS Support]

Case 1: Do a simulation with 1000 runs and take the average of this runs as your result.

Case 2: Do a simulation with 100 runs and take the average of the runs. Repeat this 10 times (9 more times) and take the average of the averages.

In case 1 you have 1000 inner loops and no outer loops.

In case 2 you have 100 inner loops and 10 outer loops.

In both cases you run 1000 simulations.

[RS Support]

Correction on the above. It should read that in case 1 you have 1000 inner loops and 1 outer loop, i.e. you only did this once.

[Massimo Barbi]

Dear Sirs,

I use BlockSim software (version 1.1 MT) to do FRED analysis for my main customer Ford Motor Company. During this experience there are two big points of misunderstanding with BlockSim concept:

Point 1:

I prepare a normal block diagram only with components, and for each components I insert Failure Data, Repair Data and Maintenance Data. After this, I build a block diagram where I use a block not as component but as “diagram” (with the option “Block as Diagram” ); the software rightly disables “failure” option because it computes the correct value for the group that I am building.
My perplexity is: Why doesn’t the software compute the Repair and Maintenance value for the group? It’s very strange, because it has got all information to do this computation: I already inserted all repair and maintenance data for each components, and why does the system ask me to insert these data manually? It’s too complex for me to compute manually these data for the group starting from components.

Point 2:

I prepare a normal block diagram only with components, and for each components I insert Failure Data, Repair Data and Maintenance Data. When I insert Maintenance data for each components, I mean that this is Preventive Maintenance, so in our cases these activities can be done when the system is off, for example at weekends, or in the night or during summer holidays etc. After this, if I run a simulation in particular “Maintainability Simulation”, BlockSim computes these Maintenance Times as a “Downtime” for my machine. I don’t think it’s correct because only if the machine works 24 hours a day and 365 days a year I haven’t got any free time to do this activities.

Best Regards
Massimo Barbi
MARPOSS SPA
ITALY

[RS Support]

The reason for this is based on how version 1 was designed -- which was based on the assumption that once one created a group, the repair actions would be one the group and not based on the components. In other words if I have a motor, it may take a certain time to repair each component in the motor (i.e. replace the motor subcomponents). However a replacement action on the motor is not really a function of how long it takes to replace individual components in the motor since one is replacing the whole motor. It may take me 10 minutes to replace the entire motor whereas it may take 2 hours to replace the coils. Thus the rationale used.

Now given the particular application that you are using it for (FRED) we are aware that the ability to do what you are asking is important. We are working to give you that option in the next release of BlockSim.

On point 2 the analysis assumes that you are running continuously and again that was the intent. What you are asking for is the ability to add phases to the system. This again is being looked at for the next release of the software.

Should you have any further questions or require more details please contact our support at Support@reliaSoft.com.

[Cidicley C. Sousa]

I´d like to know how I represent the stock in RDB.
For example, I have the system where if the equipment failed, the system continue running because has one stock with 03 days of capacity.

Regards,
Cidicley Sousa
Reliability Engineer
CVRD Company

[RS Support]

I am not sure I understand what you are asking.