# Velocity inlet: With if clauses

**URL:** <https://www.simscale.com/forum/t/velocity-inlet-with-if-clauses/36702>\
**Category:** Fluid Flow / CFD\
**Created:** [August 8, 2016, 10:42am UTC](https://www.simscale.com/forum/t/velocity-inlet-with-if-clauses/36702 "2016-08-08T10:42:01Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ajaybharish](https://www.simscale.com/forum/letter_avatar/ajaybharish/32/5_5575768a8748004e209b776fc1b2916d.png) [@ajaybharish](https://www.simscale.com/forum/u/ajaybharish)\
**Post date:** [August 8, 2016, 10:42am UTC](https://www.simscale.com/forum/t/velocity-inlet-with-if-clauses/36702/1 "2016-08-08T10:42:01Z")

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Hi,

Is it possible to define a velocity inlet condition that is time-dependent but also with an if condition? Something like

if (t \< tmin)  
v = 0  
else  
v = some function  
endif

Thanks

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<div class="post-metadata">

**Author:** ![ajaybharish](https://www.simscale.com/forum/letter_avatar/ajaybharish/32/5_5575768a8748004e209b776fc1b2916d.png) [@ajaybharish](https://www.simscale.com/forum/u/ajaybharish)\
**Post date:** [August 8, 2016, 11:21am UTC](https://www.simscale.com/forum/t/velocity-inlet-with-if-clauses/36702/2 "2016-08-08T11:21:52Z")

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I found the answer. You can define velocity inlet one as

v = 0\*(t \< tmin)

and then a second condition as

v = function\*(t\>tmin)

I believe this should work.