innovation, page-2

Its brilliant because of its simplicity. For the Leviathan example some earthwork shaping would be dead simple and longlasting. Care might need to be taken so that the enhanced flow is symmetric about the vane axis. An extra loading on the vane when passing the bottom sector might cause some knocking effect. No doubt they have worked that through.

Another example of the simple multiplier principle that you raise, Geojac, occurs for wave power with the Norwegian surge tower (oscillating water column). This has the two-way air turbine in the top and the wave surging into an aperture below. The overall electric power generating efficiency was low and almost scuttled the project. Then came the bright idea to put a pair of quarter wavelength flaps on either side of the input aperture and the efficiency instantly doubled. It was just a question of transferring what was standard knowledge from other fields (radio and microwave antennae, and optics) into water waves. This is a great justification for doing brainstorming to get ideas that are not so crazy.

As a corollary to the above can the wave amplitude be increased at the input aperture in some way? In principle, yes, by focussing the wave front. What changes the direction of a wavefront? Depth. We know that as a wave comes in towards a beach its front shifts to be parallel to the beach. Therefore some large offshore underwater plates vertically adjustable would have the same effect. Hence we have a water wave lens to focus on any point we wish.

What other examples can people think of?

In the case of geothermal power where would you look to increase efficiency?

Juke