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 MAB July 15, 2008 07:14

Time Chart of Surface Elevation

I have generated Water Waves , Now i want to create a chart of surface elevation against time(containing all time steps). Any suggestion 'll be appreciated. Thanks

 UnderwaterAlex July 15, 2008 13:54

Re: Time Chart of Surface Elevation

If I understand you correctly, in Post you could create an isosurface with at water.volume fraction = 0.5, then create an expression that finds the maximum value of a given coordinate of that isosurface (for instance: maxval(y)Isosurface 1). You could then create a chart which plots this expression as a function of time.

This will only have the timesteps which you have saved along the way. If you wanted this for every step using a monitor point in the solver, you have to try something else because I don't think you can make an isosurface location reference in Pre.

Hope that helps,

-Alex

 Glenn Horrocks July 15, 2008 22:40

Re: Time Chart of Surface Elevation

Hi,

If you want a monitor point you can either output the volume fraction at a number of points and you can see the free surface move that way, or more precision can be gained by integrating the volume fraction over a surface or volume. As the free surface moves up and down the total integral will move.

Glenn Horrocks

 MAB July 16, 2008 08:09

Re: Time Chart of Surface Elevation

Hi Alex, I tried this but nothing is appearing on the chart... :(

 MAB July 16, 2008 08:13

Re: Time Chart of Surface Elevation

Hi Glenn H. Could you please explain how to integrate the volume fraction over a surface or volume. As free surface moves up and down on any particular vertical line or plane. What i want is to plot the position of free surface over that particular line/Plane against time. i need few more tips to achieve this task. Thanks

 MAB July 16, 2008 08:21

Re: Time Chart of Surface Elevation

hi Alex. i have created isosufrace 1 . and then maxVal(y)@surface1 gives its maximum value but when i tried to plot it against time. i chosed option of expression then selected this expression .. but nothing appeared on chart..

 MAB July 16, 2008 09:29

Re: Time Chart of Surface Elevation

hi Alex , I managed to generate the plot of maxVal(y)@surface1 by pressing the refresh button on top. but this graph only show the maximum value at each time interval. while i am looking for a whole free surface probile at a particular position( which could be a line) any more tips ??

 Glenn Horrocks July 17, 2008 01:58

Re: Time Chart of Surface Elevation

Hi,

Have a look at some of the CFX-Post tutorial examples. To get the free surface level, define a boundary surface and calculate areaInt(Water.Volume Fraction)@Surface Name/area()@Surface Name. This will give you the % of the surface covered by water. You can work out the water height based on the dimensions of the surface from there.

You can also do this on a line object to give you the level at a point but I think this will only work in CFX-Post. If you want to use a monitor point it has to be the surface method.

Glenn Horrocks

 MAB July 23, 2008 05:37

Re: Time Chart of Surface Elevation

Hi Alex.. your method works fine. But i need little more tip as i want to plot the height of free surface at some particular distance x (horizontal)

 MAB July 29, 2008 06:10

Re: Time Chart of Surface Elevation

is it possible to get an intersection of Isosurface of water.volume Fraction(0.5) with a solicing plane in the domain. if yes then it would be the easiest way to achieve this time chart. please suggest something. thanks

 halilymc February 27, 2016 19:45

generate waves