How to make Rocket exhaust without Particles

Inspiration

He added two donut torus objects, and linked the wave displacement to the z motion of them?

To copy the wave look for the torus objects  use  the copy modifier and copy the location of the points of the displacement? 

 

Reference

 

This video has several different types of exhaust.

 

Beginner

 The below is a simple shader setup for the exhaust. That's a little different.

 

Intermediate

 Here is a tutorial where his idea is to add a different cone at the end part to simulate a wavy look at the tip? He also uses a color ramp for the texture

 

Advanced

This person makes a cone and displaces it.  The awesome tip is he uses the compositing to blur the just the emissive areas making a nice soft glow.  For computers with lower specs this is a completely  awesome and feasible way to make good looking rocket exhaust.

Advanced

Things to do:

Add in a volumetric for the cloud exhaust.