Tram Town
Sunday, October 23, 2005
| Category: Engineering Matt Keveney has a terrific site with animations of a wide variety of engines. I had never really quite understood Stirling engines until I was referred to Matt's site by the Wikipedia. Matt does not appear to have updated the site since 2001 but he doesn't need to, it's all there and beautiful. I am particularly inspired by the differing lengths of the compression and exhaust strokes in the Atkinson engine. UPDATE: [following a thoughtful shower] It's worth noting that when people use the term Atkinson cycle they are usually not referring to the Atkinson engine. As employed by Toyota and Ford in their hybrid vehicles, the Atkinson cycle entails leaving the inlet valve open for a proportion of the compression stroke so that some of the fuel/air mixture is pushed back into the inlet manifold. The effect of this is much the same as in the Atkinson engine with more of the energy released in the power stroke being applied to the drive shaft rather than disappearing into the exhaust as heat. It's almost like the opposite of a turbo with respective effects on efficiency. I guess one of the advantages of using this technique is that, when raw oomph is required, the valve timing could be altered on-the-fly. Now I've really scared off most of our readers. |
