In order to produce thrust based on Newton’s third law, ramjets, scramjets and rockets use a nozzle to accelerate hot gases.
As a result, a nozzle is a simple device, in particular a duct with a specific shape.
In fact for rockets this is generally a convergent-divergent to accelerate the flow to supersonic speeds. However, using only a convergent one, the maximum achievable speed would be that of sound.
Not only our DART guys are designing a convergent-divergent nozzle for their model rocket to generate the required thrust, but also they are using Ansys Fluent (industry-leading fluid simulation software known for its advanced physical and precision modeling capabilities) so they set up the simulation to analyze flow through the nozzle.
![Flow simulation with CAD softwares.](https://icarus.polito.it/wp-content/uploads/2021/03/IMG_9072-960x559.jpg)
Furthermore this was made possible by importing the geometry (previously drawn to CAD), setting the mesh of it, the physics and the numerical model.
![Mesh associated with the nozzle, using the same geometry.](https://icarus.polito.it/wp-content/uploads/2021/03/IMG_9073-960x447.jpg)
On the other hand, It should be emphasized that the simulation nozzle is still provisional until a next engine test.