Blender Tutorial - Creating a Simple Explosion Simulation

[Music] hello everyone and welcome to another blender made easy tutorial today we're going to be creating an explosion the process of creating explosions in blender is actually a lot easier than you might think all you need is three things a fast moving particle system a smoke and fire simulation and a basic material and we're going to be covering all that today let's get started by deleting the default Cube and then you can press shift a and let's add in our emitter object let's go with an icosphere now before you do anything else make sure you open up this panel right here and set the number of subdivisions up to a level of three there we go let's go into front view and delete half of these so I'm going to go into wireframe in into edit mode and let's box select the bottom half right here press X and delete the vertices then we'll move it down this is going to be our emitter object which emits all the particles which creates the shape of the explosion now before we create the particle system I want to give the surface of this a bit more randomization so let's add in a displacement modifier over here in the modifier panel I'm going to click new on that texture go over to the texture panel and switch the type from image or movie over to clouds then you can play around with the size until you get the bumps that you want and then from here we'll scale the entire thing down roughly to about a 0.4 or 0.5 on the dimensions with that done we can go ahead and create the particle system I'm going to jump over to the particle system tab click on that plus sign to create a new one and here we're going to change a lot of the different settings first off the number of particles we're going to go up to 6000 the start frame we're going to go up to 10 and the end frame we're going to go up to 15. so the particle system lasts for five frames and the lifetime of the particles I only want them to last for 5 frames as well next up let's open up the velocity Tab and we want the shape to go upwards and spread out to do this we can set the normal amount over here to a value of 4 and then the Z Direction which is up we're going to set that up to a value of 6. let's restart the animation and play it to see what it looks like so you can see here is the basic shape of our explosion you can see it's looking pretty good but it's not very random they're they're all kind of in a straight line so to fix that we can set the randomization right here up a little bit let's go 0.5 we'll then restart and play this and you can see that looks a lot better so instead of having them all in single streaks of particles that's a lot more random I might set the randomization just a bit higher let's go 0.6 and then from here we'll play it and I'm liking how that shape looks at this point we're going to add in a couple more particle system and rotate them and position them around so first off I'll press shift d on this object then we'll right click to place it right at the center we'll go over to the texture tab right here create a new texture and then just change the size this way it gives it some different variation maybe we'll rotate it like this so the particles are going to go in this direction now then we'll jump back over to here and whenever you create a new particle system you always need to duplicate it so it doesn't change the original one so we're going to click that button right there to duplicate it let's set the start frame to a different number let's go with 11 and then 16 for the end frame down here I'm going to set the random up to 0.8 I'm going to set the Z direction to 7 and the normal 2 3. just some different variations so it doesn't look exactly the same now when we play this you can see there are two particle systems now one's going off in this direction and one is going up and this is going to create the shape of the explosion from here you can do this a third time if you want different streaks going up but one thing that I'm going to do is actually add in a circle object we'll go into edit mode and press F to fill in a face and what I want here is for the particles to actually shoot downwards and hit the floor this will cause a really cool effect with the smoke so we're going to add this in we're then going to rotate it along the X so it's aiming upside down so the particles are going to go in this direction let's create a new particle system we'll set the number to 5000. we'll set the start frame to 12 and the end frame to let's go with 17. I usually like to have about five frames for the particle system then for the lifetime we'll set that to 5 and then again down here we're going to set the normal amount let's go up to seven and since the normals of this circle are pointing down we don't need to change the Z Direction just having the normal will be perfectly fine we'll then set the random up to a value of 1.5 I think that's pretty good then to have them collide with something let's add in a plain object we'll go into front view and make sure that these are above just like that and then we'll select our plane scale it up a little bit and then we're going to add Collision to this so jumping over to the physics panel we're going to select Collision set the dampening which controls the bounciness of the particles will go up to 0.7 the randomized 2.5 and we'll do the same thing for the friction I think that is pretty good now let's just double check that this particle system is actually going to shoot downwards this way and yep you can see they are I think they're bouncing just a little bit too much so let's bring the dampening up to 0.9 then we'll restart play that again and that looks pretty good so from here we'll select our Circle we'll move it back to our position and move it down just like that for the next step we're going to set up the flow objects so select one of them click on fluid and set the type over to flow then for the flow type we're going to switch it over to Fire and smoke for the flow Behavior we're going to select inflow and then for the sample sub steps since these particles are moving very quickly we need to bring this up to a value of seven for the flow Source we're not going to use the mesh we're going to use the particle system that we just created and then for the particle system select the one in the drop down menu another option that we need to check is the initial velocity this will allow the smoke to actually flow and have some velocity with the particles so when the particle moves very quickly the smoke is going to flow with it and have some initial velocity after the particle dies out that's very important we're going to set this up to a value of three and that is all of the basic settings for our flow object and then what we're going to do is copy these exact settings for the other two objects now we could press Ctrl L and click on copy modifiers but that's also going to change the particle systems so instead I'm just going to do this manually real quick for our simulation I want there to be an initial explosion of fire and then I want another explosion after the fact of probably around 50 frames later we can do this very easily by selecting all of the objects we'll select the icosphere the other icosphere and then the circle let's also move them to their own collection by hitting M moving to their own collection we'll call this explosion one then what we can do is press shift d on all these objects press M and move them to their own collection and this one we're going to call explosion 2. let's go ahead and hide the explosion 1 collection so it doesn't interfere with this one then all we have to do here is change the start and the end frame first duplicate the particle system that's very important make sure you do that for every single one that you add let's restart the simulation and play it and there's the first explosion and then I want the second one to happen at around 60. so for this start frame we're going to go 60 and the end frame we're going to go 65. then all we have to do is maybe rotate it like this so it's pointing in this direction and then we'll do the same thing for the other one select the igosphere duplicate the particle system we'll set the start frame to 61 the end frame to 66. and then maybe we'll rotate it like this so it's facing a different direction and then finally the circle and you get the idea you can do this as many times as you want throughout the entire animation you can even add more particle systems if you wanted to duplicate this circle you can so you can have one here and then you can duplicate it and have another one here but again make sure you always duplicate the particle system so it doesn't affect the other ones so what I'm going to do here is I'm going to add in this explosion then I'm going to add in one more explosion probably at around frame 110 and there we go I've now created the rest of the explosions with their own particle systems and correct frame start and end values let's take a look at it by hitting the space bar here's the first one here's the second one and then finally here is the third one so with that done we're going to go ahead and bake in this particle system by opening up the cache panel then clicking on bake all Dynamics and since we've duplicated all these objects they're all going to share the exact same settings over here and we don't need to copy them the last thing that we need to do before we bake in the Smoke simulation is to add in a domain let's press shift a add in a cube object we'll go into front view wireframe and scale it up to be the correct size right about there is pretty good I want to make sure that it matches the same height as the plane that is good just like that we'll go into front view restart the timeline and then make sure the particles are staying inside the domain object which it looks like they are so with that done we're going to press Ctrl a apply the scale then jump over to the physics panel click on fluid set the type over to domain now before we do anything else we're going to scroll down here and set the type over to all so we can bake everything all at once this resolution division value basically controls how good the simulation will look and typically with a higher resolution it's going to look like a bigger explosion in real life with a lower resolution and a higher noise value down here this is going to make it look like a smaller explosion since I'm going for a large scale explosion I'm going to set this higher we're going to go up to 256. now this is going to take a quite a long time to bake so if you have a slower PC I recommend setting this a little bit lower like 128 that's still going to look very good but if your system can handle it I recommend 256 because it's going to look really good next up we're going to turn on the bottom border collisions because remember the particles are going to hit the bottom so I also want the smoke to hit the bottom of the domain we're going to turn on adaptive domain this will also help with baking and speed up the process a little bit and then we're also going to set the vorticity of the smoke this is the amount of swirls in the Smoke let's go up to .05 we only want to do a little bit of this we're also going to turn on noise open up this panel and we're going to leave the default settings as they are finally open up the fire and the reaction speed this is how fast this the fire is going to dissipate let's go with a lower value which in turn is going to make the fire last longer we're going to set this to 0.4 and if you want to pause the simulation as we're baking it you can click that is resumable option but this is going to cause the simulation to bake a little bit longer so I'm going to leave it off because I'm happy with the rest of these settings and one quick note that I had forgotten to mention in the tutorial is the end frame right here make sure to set this to 170 we don't need 250 frames for the simulation and also while we are here let's set the end frame in the timeline to 170 as well another thing to note about this cache folder right here where all of the smoke information is being stored this is a temporary folder you can see it right there app data local temp that means when you close blender and open it up the next day all of those files for the cache are going to get deleted because it's only a temporary file so if you want to save your cash and so we you can open up the project later and not have to rebake it click on this button right here and then navigate to a different folder and save it right there once you've done that you are ready to go then click on bake all alright the simulation has finished baking and here is our result it took a little over an hour to finish it and as you can see it looks pretty nice there is a lot of detail in the smoke and the fire now if we play animation you're going to see it's very very slow and it takes a very long time to go through all of the frames so if you wanted to see how your simulation looks without having to render out the entire thing here is a quick tip for you first make sure you set up the camera like you can see here I've set it up in the front view then over in the outliner make sure you hide all the particles because if we play it you can see all the particles are right there I don't want those to show up so I'm going to just hide them from The View by hitting that little eyedropper tool right there next make sure you set an output of where you want your animation to go to and then use the file format MPEG with the encoding of MP4 and then you can come over to view and then click on viewport render animation and that's going to render an animation of your viewport which is very handy especially when working with simulations so now that I've done that here is our simulation right now as you can see it looks really cool if you want the explosion to be a little more horizontal you're going to have to rotate the particles so they're going horizontal rather than straight up but other than that I think it looks really good so now let's set up the material first I'm going to jump over to the render settings and switch it from EV over to Cycles I will be showing you how to render this in Eevee after we create the material but just to actually see what our simulation looks like without having to set up everything we're going to switch over to Cycles now to set up the material we're going to split this view switch it over to the Shader editor then create a new material we're not going to need this principled Shader so go ahead and delete that and also make sure I forgot to mention have your domain selected when you create the material next we're going to add in a principled volume Shader take the volume plug it into the volume of the material output then let's go into rendered view to see what it looks like the density of this we're going to go up to a value of 30 so we have a lot more dense smoke and then for the color we're going to drag it a little bit darker so we have more of explosion looking smoke now you can see our fire is not in our scene now there are a couple of ways to add that back in the black body intensity is one of those ways if you want to bring that up to like 15 or so you can and you can see here is the results but this doesn't really give us a lot of options for controlling the color of the flame so instead we're going to be adding in a couple of other notes first off we're going to add in a volume info node we'll place that over here then we're going to add in a color ramp place it here and then finally a converter math node we'll place that here there are two things here the density or the flame you can use either one and I'll show you the differences first off we're going to take the flame plug it into the color ramp then the color into the ADD and then the value is going to go into the emission strength we need to switch this over to multiply now this bottom value controls how bright the flame is going to be let's go up to 50. then to add in the color we're going to select this color ramp shift d it drag it down here we'll take the flame plug it in and then the color is going to go into the emission color then over here we're going to change a couple of these handles first off the handle on the right we're going to go with a light orangish color somewhere around there then we're going to add in another handle this is going to be a more of a reddish orange right about there brighten it up a little bit and then finally We'll add in one more handle this is going to be more of a darker orange somewhere around here you can play around with these and change the colors however you like and then also another thing to make the colors pop a bit more is over in these settings over here down in the color management set the look over to high contrast this is going to make the colors pop a lot more so if we go back to frame around 20 or so we're going to see the fire a lot more as you can see there and then if we jump over to frame about 40 or so we're going to see the fire dissipates very quickly that's why I don't really like using the flame attribute because when the fire disappears it's gone from the scene so instead I'm going to be taking the density output plugging that into the color app and then down here in the color ramp as well and as you can see here we have a lot more fire in our scene to clamp down on this we're going to drag this color ramp much closer to the white value somewhere around here and then we'll play around with these so now instead of the fire dissipating very quickly it's going to take the density which is the actual smoke and use that to add in the fire and I think this looks pretty nice so now if we jump over to frame like 70 or so but you can still see there's some fire right there if you don't like how much fire there is you can keep going with the color wrap drag it even closer to the to the right side something like that will look pretty good and there we go from here you can just render this out create a basic scene if you want to add some lighting you can do that and then render it out in Cycles now if you want to render this in EB there are a couple of other things that we're going to need to change so let's go ahead and get into that first thing of course is to switch over to the EV render engine if we do that you're going to see our fire looks very bad so we're going to open up the volumetrics and firstly we're going to set the tile size down to two pixels this will give us more detail in the fire next we're going to turn on volumetric Shadows that'll also help with adding some Shadows to the volume and then finally we're going to set the start and end values basically how EV renders out volumetrics is it breaks it up into different layers over this amount of distance and the amount of layers is based on the sample count So currently we have 64 layers over a hundred meter distance but the problem is our volume is only in a small section it's only about five meters across so we're stretching out all of those layers over 100 meters but we only need it to stretch over about 5 meters so what we need to do is go into the camera view and set the start to right where the volume starts so we're going to drive this up until we see the volume disappear and then we'll drag it down just a little bit so let's go with a value of 19. then the start we're going to set at the end of the domain and again since it's about five actually it's only about four meters all we need to do is set this up to around 25. so now all the layers are being compressed within those two values and as you can see there our simulation looks 10 times better if you want even more detail bring up the sample count even higher which I'm going to do I'm going to set that up to 128 and then the Shadows down here I'm going to go up to 32. we can also turn on Bloom if we want to add some glow to the fire and then if we want to add in a background you can do that as well but that's basically all you really need to do if you are animating the camera these values here in the volumetrics might not work if you're moving closer to the Smoke simulation they might not work very well so you're going to need to play around with these until you get the exact number that you need but there we go that is how you create a cool explosion in blender very easily thank you very much for watching this tutorial and if you created something cool I would love to see it so make sure to send it to me on Instagram at blender made easy if you have other suggestions for tutorials in the future let me know in the comments down below but I will see you guys in the next one

Channel: Blender Made Easy

Views: 100,262

Keywords: explosion, blender, vfx, cg, blast, simulation, mantaflow, fluid, 3d, blender 3d, tutorial, fire, smoke, blender tutorial, blendermadeeasy, blender made easy, particles, easy, explosions, cycles, eevee

Id: MxfctMsd0Ck

Length: 20min 21sec (1221 seconds)

Published: Fri Feb 24 2023