Ignitor

[hometime]

Anyone care to tell me why the plane isn't igniting?

http://www.hometime.net/ignitor.zip

Thanks,
Don

[Solitude]

Not sure for all the reasons -- I took a very quick look. Right now the plane is setting the temperature in the voxels to 0 since you have it to set temperature.. this means that anything in those voxels will change from whatever they are to a temp of 0 which means it won't ignite. Either disable temperature on the plane or change it to add 0. This should at least get you started...

[Rif]

Aright i opened the scene .. heres the things Don:

1-Your not Seeing a Clean Burn cause you have everything By default in their emiting lots of stuffs and duplicating effects on top of the other.. for what you want to achieve i would start with turning off the Render Smoke from the Rendering tab .. you want to see fire right ? well ur fire is their but hidden Under the smoke .. thats for 1

2- Even then , you ll see a small burn and thats it ... pretty agitated.. second thing you want to do is gon in your fuel Tab under simulation and Put the ingition temperature Higher ( ex:100) .. I say put it higher cause you kept the Temperature of your second source ("start Source") at 300 ..

3- then to really see your effect and setup the right "Burn State " on your voxels , i suggest you turn Off the Start Source emitor , and ANimate the boolean On active from frame 10 to 15 .. So its on for 5 frames and then stops..

4- The Other Thing and thats what i mean by duplicates is that in your start source , your emiting smoke and most importantly Fuel again .. When you r trying to Setup a "Burn Phase" , you want to keep it simplist at first so you can tweek every single details at the time based on ur desire.. So , in Short tearms , Put the Fuel of ur start source at Disabled and Kill the Smoke as well ( instead of set) ..

5- Hittin sim at this point will give u a nice Boom of fire at frame 10 to 15 and then poof dies.. now tweeking time.. Understanding that you want to produce more heat as Each Voxels gets burn , you increase the heat production gradually in ur simulation tab.. all the way till u hit 60 for exampl.. Then next thing is that youll remark fire "lenght " is Short so you wanna decrease your Burn rate till you hit 10.0 for example... Then Third thing you wanna tweek is the Expension of the Fire incrementing slowly till u hit about 60 .. Then you hit sim and what you get is actually a Fire ball at frame 10 to 15 igniting but your fire is slowly spreading to burn phase the Other Part of the fuel in your grid and it will die around 40 . After seting up properly the spread time ( heat production versus expension ration) , intensity ( fuel amount versus ignition temperature ratio) etc.. now you can start adding xtra smoke from the ignitor source , then more fuel if you want etc..etc.. just start with the basic idea than build up and remember your key settings for futur Setups..


lastly , you might want to read that post where i explained the same thing as well in probably other words : http://www.3dplanet.de/cgfluids/viewtopic.php?t=489



I hope that help ,

cheers

[hometime]

Rif,
Thanks for taking the time to look at the file and respond.
I don't fully understand all the terms and conditions you are describing
but will try to follow along with Fume open after this present render.
Just joined the CG Fluids forum and had my account activated,
but the link to the forum where you say you went through the subject,
brings up a page saying, "the topic or post you requested does not exist".

Don

[Rif]

yep .. now your on .. its a legit user for fumefx forum .. i had to check with kreso ..

cheers,
as for my terminologie.. if u read it in french , it all makes sence ! heh..

[hometime]

Thanks Rif,
Page still says the topic doesn't exist, is the link good there?
I'm sure your terminology makes sense in English
I'm just not that familiar with all the areas of the Fume rollout,
though I've been going over it for hours.
Don

[Rif]

ya stupid phpb 2.something.. i have to switch like sitni sati to 3.0 soon !

Under ffx group , go in Fume Fx - Scene Debugging .. their is a post\question about "Help Fume gets offset from emiter source".. In it i explain in other words the way expansion and temperature ignition and fuel amount helps tweek the "fire core" of a sim.. Now its a total different effect than urs but the idea is always the same.. its just important to understand what everything does and why cause their is alot of nuances .. he ..

[hometime]

k, I'll check it out.
I looked at one of your posts here on this forum earlier too but still must not be getting it.
Should get some rest so I can have a fresh look.
What I understood from your post and my reasoning is that the object to be ignited
should have the fuel set at zero and the ignitor above that
and that should cause it all to go up in flames, but guess not.

Don

[Rif]

Ur second source , ur "ignitor Source" only actually needs to Ignite ! So that means Enough Temperature to heat up the mixture to produce the explosion ( burn phase) from the fuel .. thats the logic behind it ..
thats why ui m saying it dosnt need fuel ! .. Your fuel is beeing spread from your First Source ...

[hometime]

Yeah, ok, but regardless, it's not burning, even though I have the heat and expansion wa-a-a-y up.
Unless I go too high with them, then the whole grid is full of fire on the second frame.

[Rif]

you did everything i wrote down and your not getting fire burning fuel ?

-Turn OFF Smoke rendering
- Burn rate 10
- Temperature ignition = 100
- Expension 60
- heat production 60
- Animate Active Second source from frame 10 to 15
- Turn Off Fuel and Smoke from that second source


if you do not see a burn their then their is a probleme somwhere else .. i literally did that to get a burn from frame 10 to 40 ..

U gotta remember ur scene is really low voxels amounts atm.. to get the detail you want at one point after that youll want to lower the spacing to get about 200 Cubic voxels rresolution..all though ur still going to have the burn at that small amount of voxels , the quality wont be good till you uprez..

[hometime]

No, I was just reflecting on my previous experience,
I'm still waiting for that very slow render to finish, upon which I will then go to bed.
I'll check out all your instructions after I've gotten some sleep.
Shouldn't be much longer now.

[Capitanred]

maybe the ON-time is to short. I had a similar scene once(other settings, but similar effect) and when i animated to emit fuel longer and have the expansion longer set to higher values, it burned much more. when it was set to short, i didn't get nearly any fire.

[hometime]

Ok, not quite getting how I am to animate the On/Off state of the second source.
You say,
"Animate Active Second source from frame 10 to 15"

Where are the controls you are telling me to activate?
Temperature up over 100 for those frames?
How do you determine cubic voxels?

Don

[Rif]

"Animate Active Second source from frame 10 to 15" : ? this is as simple as Turning On Max Auto Key and going at frame 10 clicking on the ACTIVE checkbox of your second source , then going at frame 15 and CLcik again On it to turn it off !! before hitting Autokey be sure you r source is actually Active OFF .. its a Normal Animation Key !


"Temperature up over 100 for those frames?" Your temperature is the same as it is in the scene u sent me ! i think it was 300 right ? then keep it their !

"How do you determine cubic voxels?" : I have NO clue what you mean by that..

[hometime]

From your post above: "lower the spacing to get about 200 Cubic voxels rresolution"
But I figured it out before rereading it, lowering the spacing.

It's hard to find a "sweet spot" in spacing, 5 is too big for the sim I'm running and 4 runs into 3 minute frames. Clicking the active selector doesn't seem to work, the selector doesn't reselect at the proper frame and yes autokey is on.

Don

[Rif]

NOnonon.. ur doing it from the FFx UI !.. Do it from the Source HElper Itself.. the source is a Helper Max Object , so select it in the scene and in its control pannel you have an On ( active) or whatever its called.. thats the one u can animate..

[hometime]

ok, I see the keyframes there but the selector wasn't active before,
thought both dialogs were the same.
Ah, I was trying to animate the USE selector instead of the ACTIVE selector.

[hometime]

Well, thanks for all the help guys, sorry to be such an annoyance!
I did get something a bit satisfying and started the source ignitor at frame zero and ran it until frame 25, this is what I got.

http://www.hometime.net/ignitor.html

[Rif]

here u go!! no anoyance at all .. it takes time to get ur head around everything.. the most important is that you understand what your doing in it.. then , your exploration of the software will most likely make you more and more happy