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Piecewise function to model time-dependant BC

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Old   April 5, 2006, 02:03
Default Piecewise function to model time-dependant BC
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Ramses Galaz
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Hi

I am in the need to model the flow of blood passing through the coronary arteries. The inlet BC should be pressure driven by a typical Aortic Pressure Waveform which is a very oddly shaped function of Pressure vs. Time as some parts are linear and some quadratic or higher order.. it would be more accurate to model it as a piecewise function.

I need to know how to define piecewise functions in CEL expressions to model the time-dependant pressure at the inlet for this transient analysis.

Thanks

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Old   April 5, 2006, 02:09
Default Re: Piecewise function to model time-dependant BC
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TB
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1)Make use of the step function. You can turn on/off an equation on a particular time range.

2)Just another suggestion. Create a 2D data with time & pressure and then import it to Pre using User Function.
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Old   April 6, 2006, 10:00
Default Re: Piecewise function to model time-dependant BC
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Ramses Galaz
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Thanks

It seems that your 2nd suggestion was better and quicker..

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