Steam Through a bendy pipe?

[Alfonse Jerome]

Hello,

I was wondering if someone could help me i have tried over the weekend to put steam through a bendy pipe and i was wondering if there's an easier way to do it? i have tried putting a few hvemitter's in the scene at each bend, or could i just put the one in there? and if so does anybody know how this can be done.

thanx for your help!!!!

[riki]

Do a bit of a search through the forums, I seem to remember someone asking about this a few weeks ago.

[Alfonse Jerome]

I've tried looking for the discussion but can't seem to find it ive looked everywhere for it, thanx for the suggestion though.:(

[jin'a]

I don't know exactly what you want.

But can't you just apply an emmiter at one end, and add a collisions thingy to the sub-div of the pipe?

Give us a bit more detail then someone might be able to help you!

Is the steam inside the pipe?

Coming out of the pipe?

I don't understand!

[hrgiger]

Yes, I"m not sure quite what you mean either. Can you see into the pipe? Because if you can't, why not just place emitters at the end of the pipe having the steam coming out?

If you can see into the pipe, you could try emitting your particles into the pipe on one end and making the pipe an fxcollision object so they don't pass through it.

[Elmar Moelzer]

Hmm if you want to show a pipe that has been cut open on the side, you coul do use an old trick:
Build a straight, flat version of the path your steam is going to take. Then create an endomorph that fits the steam- object to your pipe. Now apply a fractal- noise, smoky- type of procedural texture and animate it in the direction the smoke is going to take. Because the texture conforms to the original straight version it will follow the curves once you have morphed the steam- object into the bent- version. To bad LW does not allow for animated uv- maps yet, would make this much easier....
CU
Elmar

[Alfonse Jerome]

thanx for your reply's,

ok i'll explain a little bit more,

i have a bendy pipe and its see through i need to be able to get my steam to pass through the pipe and go through all the bends, at the moment i have put an emitter at each one of the bends so it kinda passes through but i was wondering if i could make it easier, but as i am just a beginner i may need a big explanation,

but thanx for all your help i really appreciate it a lot. :)

[WCameron]

maybe an emiter at one end, and wind effectors at the bends....
ISTR there was a way to make an emiter follow a path actually
now that I think about it..... Bah I dont have LW in front of me atm so I cant fire it up to check...
manually I suppose you could make a bunch of emmiters, one at the bigining with it shooting along the length of the pipe, another at the bend with it shooting from the first bend, then morte at each bend. if you timed it all right the particles would die when the reached the first bend and new particles would be born from the next emitter, etc, giving the illusion of it snaking along the pipe.


- Will.

[John Fornasar]

Alfonse,

Is this for a training module or industrial-mechanical simulation?

I've done a lot of steam and gas demo's, and the hassle with the morphs is that I need to show particular fittings, not the smooth welded-pipe sci-fi look.

First, I made a library of fittings (els, tees, etc), lengths of straight pipe, valves etc. The one thing they all have in common is I slice the pipe and fittings so that the "front" half (the side facing the camera) can be given a separate Surface name, allowing me to let it go transparent when the sim starts. That lets the students see the setups as they expect them to look. The rear half if modeled with the proper thickness, with both inner and outer polys.

I create my pipes, headers and manifolds using my library of fittings, copying and pasting as needed. To get the proper flow of gas through the elbow, I create a really long straight section of pipe. You have to decide how you want to present it - just a concave half for the rear, just the convex for the front, or full tube - consider render times. Here's where you'll put your fractal or whatever texture. The first time you do it, it'll be easier to subdivide the entire length of pipe, after a while, you can just knife it where the bends will be and just triple those areas to keep the size down. Copy and save a morph target.

In another layer, place your pipe over your setup, and bend at elbows, etc to fit it. At tees, decide if the flow is from the bull or the run, and just add extra sections of pipe where needed.

When I start the animation, all surfaces are opaque for easy recognition of the setup. Fade the front surfaces, turn the Valve cores (oh, yeah, model them in a separate layer) and start the fractal moving.

Whew... I just looked at the above, and it looks like a lot of work, but once you have your library of parts, it goes fast, and the only new stuff you have to model are any new controls, etc that you want to present.

[SplineGod]

To avoid the morphing I would use rail extrude to create a "steam" object. When you rail extrude you have the option of creating UVs for the extruded object.
Once you do this you can use an image sequence of fractal noise or whatever flowing in some direction.
This animated sequence can then be applied as a UV map and your steam will flow and follow turns and bends.
If you create your various parts in your library with this steam object inside but hidden you can put the objects together and use the same steam image sequence and each pieces anim should mesh together ok esp if the steam sequence is seamless.

[John Fornasar]

Larry,

Thanks, I'll try the UV's the next time I do another one.
Most of my "pipe" library is from the LW4 days (basic plumbing hasn't really changed much in the last 100 years).

The hassle I had with the extrudes back then, and the reason I used the morphs, and that Alfonse's original question seemed to imply, was that when I had one surface and I needed to show flow through the pipes starting at the beginning of a cycle was that the "flow" moved straight... that is, if it began at the bottom of a vertical section of pipe, when it hit a 90 degree elbow, instead of turning and moving in a horizontal direction, it would fill the horizontal length of pipe from the bottom up.
The effect was that the steam appeared to shoot 20-30 feet
along the bottom of the pipe and then fill it vertically. In a classroom filled with techs that know what to expect (at least, the one's with half a clue), that would be bad...
It was probably due to me being new to LW at the time, so I should probably give the rail extrude another try.

When I first played with emitters and particles, (LW6?), the little suckers were escaping from the pipe. looking like I had gas leaks all over the place (not a good thing in my business!). Having to work fast, I never revisited the emitters, though I now realize there are plenty of tute's addressing those problems... maybe in the future.

My first time morphing, I had the entire straight section of pipe heavily tripled, with a gazillion polys in it. Now, with everything modeled to scale, (and with the Knife tool, alone worth the price of the upgrades for me), I can just work along the pipe, knifing a few times where I know the elbows will be, and just triple those areas for the bends.

Alphonse -
Also, not indicated in my first response, is that by using separate sections of "steam object" with unique textures (Steam1, Steam2, etc), I can have a flow in a pipe start and stop at valves as needed. Another thing, you can grab the lower section of the "steam object" and give it a separate surface name, that way you can show the reverse condensate flow in the pipes (that is, if you are showing one-pipe steam heating systems).

John

[kramik1]

Hello,

I don't understand anything behind emitters just yet...I haven't used endomorphs etc. The biggest problem is that when you make a surface translucent and put particles behind it (using partigon, not HV) it does not show on a render. The particles cannot be seen through translucent surfaces. Has anyone else ran into this. I need to show the particles of air moving through an engine during a cutaway.

[Ivan_B]

Heres an example i made..I created two pipes, removed half of one of them (the one thats going to render).In layout I made the full pipe "unseen by camera" and made it a collision object..Placed an emitter with some velocity and upward gravity at the base of the pipe..the steam/smoke travells up the pipe bouncing on the useen pipe...When rendered all you see is the steam and half the pipe...Heres the project files.

[kramik1]

Thanks for the upload and explanation. I think I might have an easier time doing what I want now.

[jeremyhardin]

yet another take on this...

i like larry's way, but i'm a bit of a particle man myself. Nackers started to do it this way i think, and this is what i prefer.

in Modeler
so i'd create the curve to rail extrude the pipe.
keep the curve in another layer.
rail extrude the pipe as normal.
save the curve using Path to Motion.

in Layout
load the pipe.
add a null for the path.
load the motion (saved from the curve) onto the null.
add the emitter at the base of the pipe.
select the path null and make it a wind.
set it's mode to path.
set it's falloff to off.
set it's radius to 2m.

here's a movie of that, with Sprite HV's added.

[Ivan_B]

Hey people,
I like the new take on the steam, I think it would be the way to go if you had an intricate pipe line, the flow would be consistant throughout ( not relighing on velocity and gravity of the emitter...cool) you probably noticed i tried to use the wind thing but didn't like the result. The example I gave was very rough..I had a bit more of a play and tweaked the setting, and was able to get a good result..something to look out for is the particle size, if there too big they will render outside the collision pipe.

Heres a couple of preview renders.