velocity varies with time
 

HI, I am doing Design of Breakwaters by Starcd,I am trying to put inlet as Velocity varies with Time, how can I do this, instead of constant velocity?

Re: velocity varies with time
 

either use a table or add user coding in bcdefi.f

allan

Re: velocity varies with time
 

You can use a table or a user subroutine (BCDEFI). Have a look at Chapter 7 of the User Guide.

Re: velocity varies with time
 

Thanks for Answers, I have looked on chapter 7 & 8 still not solve my problem, I have two set of Data VELLOCITY and TIME, how can I Put these data on the Table of Advanced Transients on page 11 chapter 8 of STAR-G or in other way how can I process this data as inlet (incomming velocity as function of time). thanks Aly

Re: velocity varies with time
 

To make boundary velocity a function of time, you need to use a table or user coding, as already stated. This has nothing to do with the Advanced Transients input window, shown on page 8-11 of the User Guide. That window is for setting up the timestep and so on of your transient run.

You need to set up the table using the table dialogue, and link to it in the boundary definition. See page 2-14 for how to set up tables and page 7-13 for how to activate the table in the boundary condition.

Re: velocity varies with time
 

I want to input a wave velocity which varies with time by a sunusoidal function [v=sin(wt)].

The questions are:

1- Should I put this as components in x and y for Star-CD to understand or it will understand by itself if I put just (v). 2- If it is x and y, is it realistic to put these as independent variables. Because I only see that option in the star-CD.

Thanks.

Re: velocity varies with time
 

Why dont you use the subroutine and put in you formula. It it very easy to do. Just try it.

here an example of BCDEFI

..... PI = ACOS(-1.0)

IF (IREG.EQ.1) THEN U = 3.0*SIN(2.0*PI*TIME) V = 2.0*COS(3.0*PI*TIME) ENDIF

..... RETURN END

U and V are the velocity components, TIME is already available and x,y,z are the global coordinates.

Re: BOUNDARY CONDITION
 

Hi, Iam working with transet problem, Ihave define mdel boundary as this view 0 0 1

replot

bzone 1 all

view 0 0 -1

replot

bzone 1 all

rdef 1 symp

bset all

bdis on

view 1 1 1

replot

bdis off

view 0 0 1 Problem is that Iwant to define other two boundaries Inlet on one face and wall in middle of my model where there is obsticle, How can Ido that? please any one can help? chang

Re: BOUNDARY CONDITION
 

try using VSET NEWS EDGE and BFIND commands?