Specific jet engine flame

[galgot]

Hi , Would like to submit a small problem I run into.
Trying to simulate flames from a jet engine as per this reference :

Did something very simple with two tubes modeled roughly to the shape of the flames, on inside the other , like so :

These two tubes each have custom emission shaders like so :

each have his own, just different by the colour of the flame , one bluer than the other…
Now , it looks how I like it enough when I render it :

problem is as soon as I use a view with the flames being in line one in front of each others, the inner faces of the flame tubes appears as solid

This happens too if I just use one tube to make a flame…

There is a nice solution by member moony on this thread:

How do I make a sci fi thruster flame?

Depends exactly what type of thruster you are looking for, a straight ‘cone’ type or a pulse type thruster.

using a Spherical Gradient Texture on a plain tube. But it’s not exactly what I want, cause it doesn’t make flame tube (which is specific to the engine I’m trying to represent) , but more stretched sphere with several layer of lights…

Anyone know how I could solve that ? Could a render setting do it ? or just another completely different way of doing these flames ?

[insolitus]

Try using a mix between emission and transparency instead. I’m not sure if I understand your shader tree but it could be that you emit black and not transparent in the far edge of the flame.

[zeauro]

You are using overlapping geometry. That is not ideal when working with volumes.
It is better to always use a texture to determine density.
Not necessarily a procedural one, You can use a point density one.
Modeling a hole in a volume rarely gives a good result.

But here, maybe, simply increasing Transparency bounces may solve the problem.

[galgot]

Indeed , just increasing the Max transparency Light Path to 25 did the trick

No solid flames now:

Thanks a lot !