transient simulation
 

transient simulation:
does anybody know how the appropriate total time in transient simulation would obtain? why the results alternative and
change by changing total time? the domain length is 8m and the average velocity is 0.09m/s.

Very strange question!
Could you explain better your problem? Generally the total time of a transient simulation is not a problem. You can define a total time as you want. Checkink your results you can undestand when the field is "totally developed".

Hello Katayun,

would you be able to provide more details?( e.g. fluid type, boundary conditions). however, in a simple channel it is better to do a steady state modelling to converge towards a fully developed solution. the same results by transient might take much longer to obtain.