Blender 3D is a free and open source 3D application. It is incredibly powerful.
Its modelling is great at creating many different kinds of shape. However, Blender 3D (in the current version as of this writing) is not fully capable of producing high-precision models required for engineering transfer, tooling and manufacturing-downstream processes. So for Industrial Design 3D modelling, a dedicated CAID modeller such as Rhino3D is still better.
Studiorola provides a Basic 3D Modeling Course that is based on Blender as the learning platform for polygonal modeling.
Blender 3D has a very good rendering capability. It has a good internal Raytracer as well as the ability to integrate with free high quality Global Illumination Renderers such as Yafaray and Luxrender.
Additionally, Cycles render that come with it is simply fantastic. This is as illustrated below.
In addition to that, it sports powerful animation ability. For industrial design, we most probably only need to use a fraction of Blender’s animation power. This include tools such as key framing and path animations. Blender 3D comes in versions for Mac, Windows, Unix and Linux.