Intro to Smoke Simulations in Blender | Cryo Tube Tutorial

oh hey guys today we're going to jump into blender smoke solver and break down this smoke effect I have a full time lapse of me constructing this scene on our Channel but this video is just going to focus on the smoke settings and material let's get started today I'm using blender 3.3 but I believe these settings should work for anything above 3.2 here is the scene that I put together I built most of this cryotube by hand and the environment is completely kit bashed with free 3D models from CG Trader I'll have links to those models in the build video so my goal for this effect was to have a cryo tube-like object filled with smoke and then the tube is lifted to reveal a special object of some sort in this case a cute Rocket toy and then the smoke would collapse over the base of the cryo unit and then just fall to the floor so once I had the rough geometry and animation in place as you see here I animated the camera and moved into the simulation phase and as you saw in the final result I decided Midway through that I wanted to have this action at the end so the glass of the crowd tube would move up the smoke would fall to the floor camera stops and after a beat the rocket would ignite so we'll go into those settings at the end okay so getting started with smoke in blender is super easy the fluid gas physics solver that's built into blender is a foxhole simulation system so similar to my fluid tutorials if you've seen those it consists of a domain and a flow at minimum the other objects could include effectors and force fields to set up those items I'm going to start with the emitter I wanted the smoke to originate from two locations within the glass tube as if there were like cold events on either side of the rocket so let's build that I'll start with a curved Circle move that into position and then I will fill the shape I'm going to leave the object pivot here in the center and move the geometry over I will be using the mirror modifier later with that in position we're going to add the solidify modifier as a smoke emitter or flow object the smoke can emit from an object's surface or volume or both I'll be using the surface so I'm going to add some thickness and then let's mirror okay perfect so we have our emitter using the blender quick effects menu you can quickly set up our smoke domain so I'll select the object click on object quick effects quick smoke before we hit play I'm going to go to The Domain settings and use the replay type I'll also turn on is resumable and then unicash all right let's check this out so that's kind of neat we have some tweaking to do but it's that simple to get started with smoke simulations alright so let's make some changes starting with the emitter or flow object I'm going to go through the settings for this effect but as with any tutorial I suggest you play around with the options and have fun discovering what you can create let's increase the density to 10. I want this to be very thick smoke and I'm going to animate this down to four from frame 180 to 240. I'm animating some values so that the smoke dissipates after the tube is lifted for surface emission I'm going to increase this to 6 and then at frame 240 I'll have it go to one this will emit smoke away from the mesh surface and I want to create a larger smoke source for the start of this Sim and then lastly for the flow object I will use the initial velocity and have it shoot the smoke up in the z-axis at a rate of 8 meters per second and then I'll ramp it down to 0.5 at frame 240. similar to the surface emission this will fill the tube fast and keep it filled until the tube is lifted now before we preview these changes I'm going to click on the domain and change our resolution to the final value of 260 and I'll enable adaptive domain this feature is awesome and it actually allows the domain to scale with the size of the simulation resulting in a much more efficient Sim process while maintaining your resolution alright as you can see we're getting a very soft round smoke cloud which is the style that I want for this effect now let's tweak the domain firstly I want this smoke to react to the forces and effectors in a slower than normal rate to give it a nice roll-off look as it falls down so let's change the time scale to 0.5 this will allow the smoke to still look very dense but react as if it's very lightweight under the gas settings we're going to lower the buoyancy density to negative 0.75 this will allow the smoke to sink instead of Rise I'll also use a heat value of negative one now this setting Works in tandem with the flow temperature but since I left that at the default value of 1 a negative value here will actually allow the smoke to sink after emission and then to add some minor turbulence we're going to use a vorticity value of .05 we are going to use the dissolve options and that will remove smoke from the simulation over a specific amount of frames I don't want it to be too quick so I'll use the value of 120 and I'll keep the slow option enabled which gives the removal of the smoke a lingering type of feel lastly we're going to set up our cache I'll use the unicache format and although my timeline will start at frame 100 I want the smoke to pre-sim so I'm going to use a range of 60 to 440 and I'll use the all type so we can use the bake function and then I'll pick a cache location and now before we Sim you know a major aspect of this effect is the tube that contains the smoke so I'm going to add the Collision objects I'll select the cryoglass mesh and enable fluid and select affector it'll use the Collision type by default which is what we want and the only thing I'm going to change is because this object's very thin I'm going to increase the surface thickness this will expand the Collision wall so it's more easily detected by the Sim resolution we're using and then I'll add the default Collision properties to the rocket and the base of the cryo tube and let's Sim [Music] okay so I canceled the Sim after a few frames to show you an issue we're having since the smoke is being emitted into a closed shape once the domain adaptively expands to larger than the enclosed shape blender tells the simulation to stop calculating so you can see that the smoke shape freezes after frame 73. this isn't really a glitch but it isn't what we want So to avoid this we're going to adjust our domain to intersect the closed cryo shape Just a Touch so that it never expands beyond the tube and causes the simulation to stop we aren't really seeing this rear wall of the cryotube so even if there's some false collisions happening we aren't going to see that from the camera view now when we Sim it will keep calculating the smoke until the tube is lifted so I'll resume the Sim and we'll take a look when it's done that took about a half hour and it's looking great I'll switch to the rendered View and we can adjust our material settings [Music] I'm going to use the density attribute and plug that into a color ramp [Music] and then multiply that to scale our density values Now using the color ramp I can clip the density highs and lows I'm also going to tint the smoke to a bluish color and then in the render settings I'm going to reduce the volume step rate to add more detail to the volume look this will increase render time but I think it's worth it here alright I haven't forgotten so let's get to the rocket engine so I'll create a new scene in the same project I'll add a sphere I'm going to scale it down a touch and then smush it and then as before we're going to use the quick smoke option and then in the flow settings I'll change it from smoke to Fire and smoke I'm going to add some density and increase the fuel to increase the flame size for this I will also use the volume emission and that will emit smoke and Flames from the interior of the mesh as well as the surface and then for the initial velocity I want this to shoot downward so I'll use a value of negative 2 meters per second in the z-axis okay and then for the domain we're going to lower the shape that way it'll capture the Flames as they shoot downward for now I'll enable adaptive domain I'm going to increase the resolution to 120 and that just fit the look I was looking for for a miniature rocket I'm going to increase the time scale to two so that it's a faster reacting Sim and then under gas I want the smoke and Flames to disappear quickly so I'll use a value of 6 for dissolve we're going to use a little noise so I'll keep the factor at one that'll add some fine detail to the flame and smoke shapes and then I'll reduce the reaction speed of the fire to 0.25 so that the Flames aren't too turbulent and then I'm going to change our cash range to 340 to 440. so that lines up with the engine start we want in our animation I'll select a location switch it to all and then use openvdb because we're going to actually import this into our other scene all right so let's see what we have foreign [Music] but we aren't missing our wind so I'm going to add a wind force field object I'll point this downward and I'm going to increase its strength to six then I'll position above the emitter and let's resim okay now this is what we want uh before I finish baking we need to remove the Adaptive domain now I do love this feature but because we're going to import the openvdb sequence the origin point will change as the domain grows so to keep it as a consistent starting point we're going to disable it and then I'll resim okay with that finished back in our original scene let's import and open VDB volume object and I'll select that sequence [Music] and in settings we can enable sequence and I'll change these values to match our frame range [Music] now when I hit render it'll pop up here and getting out of that render view now we just need to scale and position it to where we want [Music] foreign [Music] thank you for the material we are using a mix Shader the first is for the smoke and the second is an emission Shader using the flame attribute I plug that into a color ramp same idea as before where we can clip the flame strength and then I'm mapping those values from white to Orange to Black for the emission color and everything is ready to render I'm very happy with this result and I learned a lot along the way I really enjoy working with Dynamics and simulations and blender there is just so much you can do so please have fun playing around and let's take a look at the final result one more time uh thanks for watching I hope you enjoyed this video uh if you have any questions drop a comment below and consider liking and subscribing to our Channel and we'll see in the next one [Music]

Channel: Pixel Planet Studios

Views: 23,303

Keywords: blender, 3d, animation, cryo, tube, smoke, simulation, mantaflow, tutorial, how to, education, intro, introduction, sim, sci-fi, chamber, cg, cg tutorial, learning, blender3d, gas

Id: ielqS1hkoLc

Length: 12min 20sec (740 seconds)

Published: Fri Mar 03 2023