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The Phoenix Source nodes can use an Emit Material assigned only on those faces which will be used for emission of fluid.

Select the Box geometry and go into Face Selection mode.

Select only the top faces which will be used for the emission and assign them a new Lambert material. Change its name to mat_emit.

Go to Create Panel → Lights →Directional Light in the scene.

Exact position of the light is (X, Y, Z): (0, 300, -41).

Set the Intensity to 5.

Add a Phoenix FD → Create → Fire/Smoke Source. The Fire/Smoke Source is a Phoenix helper node used to tell the Simulator which objects in the scene will emit, how strong the emission will be, etc.

Add the Box primitive into the Fire Source's Object Set.

The Object Set of the Source is used to specify the geometry in the scene that will be used to emit fluid into the Simulator.

With the Phoenix Source selected add the mat_emit material to the Emit Material slot.

We want to Modulate the Smoke Opacity with Grid Texture UVW, so let's go to the Phoenix Simulator → Output rollout and enable the Texture UVW.

To enable the GPU Preview as seen in the video, select the Phoenix Simulator → Preview rollout → GPU Shade Preview → Enable GPU Preview.

Without re-running the simulation, here is the Viewport Preview showing the result of the simulation so far.

Our final goal for the simulation is a smooth, natural-swirling, cigarette smoke look. So all of the following steps aim at this goal. Now the smoke appears to be running too fast.

To slow it down, change the Time Scale from 1.0 to 0.7.

Here is how the simulation looks so far.

Create Phoenix FD → Create → Turbulence.

Position to (X, Y, Z): (0, 0, 0).

Set the Strength to 40.0 and the Size to 2600.

Reduce the Fractal Depth to 2.

The Turbulence is used to bring more swirls in the smoke. You can use the Preview rollout's Force preview in order to see what velocities the Turbulence adds to the simulation. Note that you have to turn off the GPU preview in order to see the forces.

Then, go to the Phoenix Simulator and run the simulation again.

Here is a Viewport Preview showing the result of the simulation so far.

To preview exactly how the TexUVW mapping looks like, go to the Simulator → Rendering rollout and click on the Volumetric Options. In the Smoke Opacity rollout change the Based on to Texture.

Plug a Volume Noise Texture in the Texture slot. Change its name to "volumeNoise_test".

Then, scroll to the Effects rollout and enable Invert.

Here's a rendered animation so far.

Now, let's Modulate the Smoke Opacity.

Set the Smoke Opacity to be Based on Simple Smoke.

Enable the Modulate option.

Keep the Volume Noise texture that we used in the previous step and change the following settings:

Threshold to 6.0.

Ratio to 0.5.

Depth Max to 2.

Time to 1.0.

Frequency to 0.3.

The images illustrate what the Modulation does when you modulate smoke with a Volume Noise Texture. On the left, we have smoke's opacity Based on Simple Smoke channel data. When Modulate option is enabled, and there is a Volume Noise Texture in the Texture slot, it multiplies the Noise texture to create the final image on the right. You can think of it as if we are using a mask over the Volume Noise Texture in order to keep only the "islands" inside the smoke volume and remove the ones which are outside the simulated smoke. This is how you get this wispy smoke result. The key is having most of the Volume Noise Texture black and keeping only these high contrast spots in it, which are dragged along and stretched by the fluid.

Here is a Viewport Preview showing the result of the simulation so far. You can see that currently there is an issue in the video. Some smoke areas are appearing out of nothing during the animation. This is because as the fluid travels through space, it meets new "islands" of opacity and starts dragging them along, which makes parts of the fluid suddenly appear.

Here is a rendered animation of the simulation so far.

To achieve a better swirling motion in the simulation, we can change the conservation mode and increase the Conservation Quality parameter under the Dynamics rollout. Set the Conservation Mode to PCG Symmetric, Quality to 50.

The PCG Symmetric conservation mode is ideal for smoke simulations or explosions because it tends to produce strong conservation which needs less conservation quality in order to look realistic. This method is also used for the Cigarette Smoke quick preset. So we choose this mode.

Go to the Fire/Smoke Simulator, and run the simulation again.

Here is an animation showing what we've achieved so far. You can see the better swirling and rolling of the smoke. The behavior is now more like that of a thin smoke.

Now, in order to make our animation more interesting, we can animate the Time Scale. This section of the tutorial is optional – you may skip to the Rendering section below.

To create the bullet-time effect, open the Dynamics rollout of the Phoenix Simulator and animate the Time Scale parameter as follows:

Frame 0: 0.7
Frame 100: 0.7
Frame 130: 0.3
Frame 145: 0.3
Frame 164: 0.7

The Time Scale is a global multiplier for the dynamics of the Simulator. Reducing it uniformly scales down all sources of velocity in the simulation.

Now we are ready for the final simulation. Go to the Phoenix Simulator → Simulation rollout and enable the Use Timeline Stop Frame. Press the Start button to run the simulation.

Now that our simulation is ready, let's render the full sequence from frame 0 to 200.

And this is our final animation.