residual in fluent

This is one of the best questions that anybody has posed in a while. As you've seen, it is sometimes not simple to declare convergence. Something that may help get the residuals down more, is to switch to double precision, and tweaking relaxation parameters may also help. Also, you need to consider the differencing scheme that you are using, and how accurate your initial flow field was. Something that sometimes helps is to get 0.0001 convergence on first order upwind differencing first, and then switch to higher order to see what it does. With external flows, where the initial flow field is normally a very good solution everywhere except near the body, it may also be difficult to get the requisite 0.001 convergence. For other flows 0.001 may not even be good enough. Take a very good look at how your surface integral changes with more iterations, sometimes if you really zoom in (in terms of y-axis scale), you can readily identify a damped oscillation, which is a good indication that you are "straddling" a converged answer. As last resort (or maybe that should be first?), work on your grid quality. If you have a number of skew or very high aspect ratio cells, perhaps away from your surface of interest, it may not affect your surface integral, but could affect the residuals.

http://www.cfd-online.com/Forums/fluent/44710-convergence-residuals.html

from bukit indah to singapore

visit jusco in tebrau
ohor的Bukit Indah离second link不远，属于新山的新区，新区的亮点就是人少，有个AEON购物中心，里面除了诸多商场外，还有一个电影院和超市吉之岛。另外距离AEON 10分钟的脚程，还有TESCO和Giant大卖场。额外突出的好处是Jurong East地铁站可以直接搭Causewaylink CW3 通过second link 直达Bukit Indah。 

just arrive in jurong east mrt, then you take causewaylink CW 3, after passing through 2nd link, you can arrive in bukit indah. then back, you just wait for CW 3 then you can go back  to singapore d . 

Residual

The residuals are the error magnitudes for equations as iterations progress. The equations include the governing equations; I.e. the Navier-Stokes momentum equations for each direction (x, y, and z if 3d, or just x and y if 2d), the continuity equation (conservation of mass), and if heat transfer is applicable, the energy equation. The equations may also include equations of the turbulence model defined under models-viscous. The residual is the difference between the previous result and the current result. As these errors are decreasing the equation results are reaching values that are changing less and less. This is what is known as convergence. That is the solutions are converging. If these errors begin to increase, the solution is then said to be diverging. Let me give a simplified example of convergence: Initial value = 2, 1st iteration value = 1.5 (residual value is equal to 2 - 1.5 = .5), 2nd iteration value = 1.2 (residual value = 1.5 - 1.2 = .3), 3rd iteration value = 1.05 (residual value = 1.2 - 1.05 = .15),... 1000th iteration value = 1.00001, and 1001th iteration value = 1.000005 (residual value = .00001 - .000005 = .000005). Perhaps the solution is converging to a value of 1. An opposite trend could be given as an example of divergence. A solution can converge and then diverge or vica versa. Does this help? Is my explanation clear and accurate?

http://www.cfd-online.com/Forums/fluent/28009-residuals.html

Abaqus debuggin

decide to use abaqus for FEM analysis.

so here is the link for compile the fortran.
http://tuoonline.sinaapp.com/?p=131

The whole picture is in fact very simple: subroutine is written in Fortran as *.f files, and ABAQUS need to compile these *.f before using it.  in this case,  the ifort.exe is the compiler. So (1) we need the the access to ifort.exe. Furthermore, this ifort.exe cares a lot about the working condition, he actually have an assistant to build up the working place for him. This assistant is called ifortvars.bat. So (2) we need the access to this ifortvars and(3)make it work!

to do (1) and (2), we need to add the file path of ifort.exe and ifortvars.bat into environment variables (path), so we can access those two at any folder while using command window.

(A)

Search your C:\ for ifort and ifortvars’s path first, record it in a text file. usually the ifortvars is in:

“C:\Program Files (x86)\Intel\Composer XE 2013\bin”

and the ifort is in:

“C:\Program Files (x86)\Intel\Composer XE 2013\bin\intel64”

.

(B)

To setup environment variables:

right click on “computer”

choose properties

choose “advanced system setting” at the left upper area of the current window

click on environment variables at right lower corner of the current window.

Choose variable “path” in the upper frame titled “system variables” and click “edit”

at the end of variable value, add these paths of your “ifort” and “ifortvars” you just found at step (A), for example, mine is:

;C:\Program Files (x86)\Intel\Composer XE 2013\bin;C:\Program Files (x86)\Intel\Composer XE 2013\bin\intel64

Attention: don’t miss the ; at the start of these text and replace my file path with your file path.

(C)

To do (3), we need to add ifortvars.bat into ABAQUS command batch file, so it could setup the environment every time ABAQUS runs.

Open your ABAQUS commands folder, usually at C:\SIMULIA\Abaqus\Commands

right click on abaqus.bat, choose “edit”.

You will probably see this:

@echo off
“C:\SIMULIA\Abaqus\Commands\abq6131.bat” %*

just change it to this:

@echo off
@call ifortvars.bat intel64 vs2012

“C:\SIMULIA\Abaqus\Commands\abq6131.bat” %*

save it.

Remember to change the bold part(intel64 vs2012) accordingly to your system type and software version. For example if you are using visual studio 2010, then vs2012 should bevs2010. I add this note because last time my friend Clay stuck on this tiny part and pissing in the wind checking system variables and fortran compatibility for 10 mins and cried.

Another note: if you run ABAQUS and saw the composer is working, but in the next line it says file or path did not find, please check the quotation marks in the line: “C:\SIMULIA\Abaqus\Commands\abq6131.bat” %* of abaqus.bat is correct, especially after you copied this line from my blog. In this case the quotation marks had been replaced by a kind of quotation marks unrecognizable by windows.

(D)

To verify if it works:

open a command window by type cmd and enter in the start menu.

type:

abaqus verify -all

this command will run a comprehensive test for abaqus, including the standard and explicit with subroutine mode. Just read what’s on screen and perhaps the log file, you will see what your ABAQUS is capable of.

SO today practice ANSYS 16.2 crack file.it is kinda headache,
but at the end of days, I realize that actually you do not need to edit the license file. you can just connect it. then it will work itself.
https://johnkaisercalautit.wordpress.com/2013/02/14/how-to-fix-ansys-workbench-flexlm-error/

Step-by-step guide:

1. Run Server ANSLIC_ADMIN utility (as administrator)

2. Click Stop the ANSYS, Inc. License Manager

3. Open command prompt and enter netstat -a. Scroll down and you should find port 1055 in use.

4. From the ADMIN Utility, click Specify the License Server Machine

5. Click Edit Selected Server Machine

6. Change ANSYS FLEXlm port number to any port number other than 1055 (ex. 1056) and click OK

7. Go to the folder \Program Files\ANSYS Inc\Shared Files\Licensing and open license.dat using notepad. Change the port no. to the one you set above and save.

8. From the Server ANSLIC_ADMIN utility, click Install the License File

9. Browse for the edited license.dat file

10. Click Start the ANSYS, Inc. License Manager

ansys fixed

what the hell.
today morning wake up fixed the flexnet problem for ansys.
https://johnkaisercalautit.wordpress.com/2013/02/14/how-to-fix-ansys-workbench-flexlm-error/
Step-by-step guide:

1. Run Server ANSLIC_ADMIN utility (as administrator)

2. Click Stop the ANSYS, Inc. License Manager

3. Open command prompt and enter netstat -a. Scroll down and you should find port 1055 in use.

4. From the ADMIN Utility, click Specify the License Server Machine

5. Click Edit Selected Server Machine

6. Change ANSYS FLEXlm port number to any port number other than 1055 (ex. 1056) and click OK

7. Go to the folder \Program Files\ANSYS Inc\Shared Files\Licensing and open license.dat using notepad. Change the port no. to the one you set above and save.

8. From the Server ANSLIC_ADMIN utility, click Install the License File

9. Browse for the edited license.dat file

10. Click Start the ANSYS, Inc. License Manager