Learn how to use Computational Fluid Dynamics (CFD) to enhance your 3D printed designs for free using cloud-based software like Simscale. Follow a step-by-step tutorial on optimizing a part cooling fan duct for a 3D printer, covering account creation, fan duct modeling, geometry addition, simulation setup, and air flow calculations. Explore particle traces, understand limitations, and view various simulation examples. Gain practical insights into CFD applications for 3D printing enthusiasts, overcoming the need for powerful computers and complex engineering knowledge.