Fluid's field speed problem.

[Giap]

it depends on the movement. For example, you can increase the sim scale from 1 (default) to 2 or maybe higher. Usually, I let my sim scale at 2. If you want to change the weight of the fluid like if you want it flies up faster, the buoyancy is the one you need to increase and vise versa. Don't increase too much though, cause it will explode the velocity.

I only use field for my specific direction I want it to move. For example, if a pipe shoots a smoke or flame. I may live the boyancy at defaulf and add a Volume Axis to flow my fluid. I'm still playing with Maya fluid and so far that all I know to answer your question.

[dim1984kimo]

thanks!

where is the attribute of scale? I didn't see anything related with it.

Am I blind?

[Giap]

Open the fluid attribute. Find the tab name Dynamic Simulation. Simulation Rate Scale was the one I have mentioned. The more you increase the more your sim will move quicker.

I've checked your image. It becomes weird because the velocity is exploding. As I mentioned in the first post. The velocity in fluid is really sensitive. You need to balance it and compensate the movement with Fields. I experienced this weird behavior before. Check this out you will understand more.

http://www.vimeo.com/3738395

[dim1984kimo]

Open the fluid attribute. Find the tab name Dynamic Simulation. Simulation Rate Scale was the one I have mentioned. The more you increase the more your sim will move quicker.
http://www.vimeo.com/3738395

Thanks again!

But what attribue is the opposite to velocity?

it is kind hard to find a balance, becoz I also want it get high speed.

[dim1984kimo]

somebody help me please. :(

[Giap]

there is nothing that is opposite velocity. The velocity is the speed.

[dim1984kimo]

hi,

Maybe something misunderstand between us.

If I want speed become very fast, it should be box's shape like the picture I post on top?

Is it any possible to make it speedy and no velocity exploding?

[dim1984kimo]

http://rapidshare.com/files/234444187/VFXm_comparison_1.mov

here is a test movies, it could be a demo example to tell it apart.

[DJ_]

Yeah... that is a pickle!

I have this problem all the time. According to Duncan it is because when you have fast moving fluids, they can sometimes move more then a voxel per frame and that kinda makes Maya "lose count" on some parameters. The 2 workarounds I normally use (depending on the case) are:

1- Cache the fluid with oversampling (sampling every 0.5 or sometimes 0.25 frames)

2- Cache the slow moving fluid but for twice as long as I need it, then scale the cache file by 0.5 (in cache settings) so it moves faster.

I really hope we can get a newer, upgraded version of maya fluids soon. Not that the one in maya is bad, but there are some things that could be better. Like the bug you've got and like how it loses the texture coordinates after a few frames when you set it to grid. Fume FX has a much better looking texturing algorythm.

[dim1984kimo]

nFluid !?

it sounds great.

it's time to beat Pyro and others.

long live Maya.

[Aikiman]

I havnt seen your problem video yet but what I use that really helps me is to turn on the velocity draw arrows. A magnitude of 250 is a bit excessive generally. I go no higher than 25 normally and if I need some initial velocity first, then I play the fluid about 10 frames with the field at work, then set initial state to get some nice little yellow arrows in my fluid.

If you need to control any velocity that is out of control you can try increasing the dampening in the fluid or for localised dampening use a drag field to slow it down in areas.

Yiu can also use setAttrs to apply velocity to your fluid but that is really a uniform approach like the wind tunnel examples in visor. I prefer just using a field because you have more control.

Like I said before though, make sure you turn on your little yellow velocity arrows.

[dim1984kimo]

Thanks!

My problem has solved, thanks to all.

:)

[CGTalk Moderation]

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.