I am new to Vensim and could use some help.
Lets say I have a part, call it bearing. It starts off with a 100% condition. I set a rate, call it wear. It starts off with 1 (0-100 min-max). Simulation steps are in weeks.
So far, simulating gives a linear slope of the bearing condition. From here on I get stuck:
I want to introduce a level, call it oil level. It starts off at 100, and is empty at 0. As this level goes down, I want the "wear" to increase exponentially. This should result in that the bearing condition no longer remains linear.
+ What does the "auxiliary" do? How does it work compared to constant or level.
Thanks
New user, simple questions
New user, simple questions
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Re: New user, simple questions
It might be better to take a step back and go through some of the tutorials.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
On this page you will find a really good Vensim PLE tutorial.
http://www.public.asu.edu/~kirkwood/sysdyn/SDRes.htm
On this page you will find a really good Vensim PLE tutorial.
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
Re: New user, simple questions
wear rate = EXP(k*oil level) is not what you want, because it's increasing in oil level. You might try something like
wear rate = normal wear rate*EXP( wear sensitivity*(oil level - critical oil level) )
with wear sensitivity < 0.
Another alternative would be to use a lookup, like
wear rate = normal wear rate*effect of oil on wear( oil level/normal oil level )
wear rate = normal wear rate*EXP( wear sensitivity*(oil level - critical oil level) )
with wear sensitivity < 0.
Another alternative would be to use a lookup, like
wear rate = normal wear rate*effect of oil on wear( oil level/normal oil level )
/*
Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
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Advice to posters (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Blog: http://blog.metasd.com
Model library: http://models.metasd.com
Bookmarks: http://delicious.com/tomfid/SystemDynamics
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Re: New user, simple questions
it works, thanks guys.