Learning Forum

[jmt714]

Hi, 

I want to apply a perpendicular and simple movement to a surface. For each time step I have the displacement. For example:

 

t      y

0     1

0.1  2

...

 

Therefore, I am using a transient table, a .porf file. However, unlike the udf files, the movement is applied using a reference, the global axis. Thus, the movement is not perpendicular to the surface. The only solution I've found is to align the surface perpendicular to the Y axis using spaice claim. However, this is no longer useful at the moment I want to apply a movement to more than one surface at the same simulation. 

I would like to find a better solution than align each time my geometry. 

 

Thank you in advance, 

 

[Rob]

Have a look at the various in-cylinder (IC) examples as that's how the valves move: check YouTube first. 

[jmt714]

Hello rwoolhou, 

 

thanks for the reply. The problem is with the in-cylinder method you need to define the motion in function of the crank angle. Unfortunately I don't have this information, it is a simple surface which moves perpendicular to axis where a I have for each time step, the final position of the displacement. Therefore I am not sure if the in-cylinder method is the best one. 

 

Thanks in advance,

[Rob]

It is, but isn't that the time of operation and not the angle? 

[jmt714]

The table I attached in the first post as an example, the first column is the time (in s), and the second column is the mm shifted from the origin.

 

Many thanks!

[jmt714]

To clarify, I would like to impose the local movement in function on time not to the crank angle. It is just a surface that goes up and down. 

 

Sorry for the inconveniences, 

[Rob]

Yes, and how do they define the motion direction in the IC models? 

[jmt714]

Hello, 

 

Looking in Ansys Fluent User's guide I guess using the IC output controls dialog box. However, I don't know which values I have to set in IC settings such as crank shaft speed, crank period, crank angle step size...

 

Many thanks,