How to define a periodic piecewise function for inlet velocity in UDF

- September 23, 2020 at 12:14 pm
  
  lytsophy
  Subscriber
  
  Dear all,nI would like to ask how to define a periodic piecewise function for inlet velocity in UDF.nthe function can be like:nv=f(t), (n=0,1,2,...)n0.07n<=t<0.07n+0.02, v=1n0.07n+0.02<=t<0.07(n+1), v=0nthanks a lot!n
- September 23, 2020 at 2:21 pm
  
  Rob
  Forum Moderator
  
  I've done this using a mix of IF statements, sin(t) and floor https://www.programiz.com/cpp-programming/library-function/cmath/floor I'll leave you to work out the maths! n
- September 23, 2020 at 4:01 pm
  
  lytsophy
  Subscriber
  
  I have solved this problem already~n
- September 23, 2020 at 4:07 pm
  
  Rob
  Forum Moderator
  
  Excellent. Please post the solution for others to learn from. n
- September 24, 2020 at 9:11 am
  
  lytsophy
  Subscriber
  
  Thanks a lot!nthe code could be like:n#include udf.hnDEFINE_PROFILE(inlet_velocity,th,i)n{nface_t f;nbegin_f_loop(f,th)nreal t=(CURRENT_TIME-floor(CURRENT_TIME/0.7)*0.7);n{nif(t<0.2)nF_PROFILE(f,th,i)=0.01;nelsenF_PROFILE(f,th,i)=0;n}nend_f_loop(f,th);n}n