ESMAR Engineering

Introducing the vanishing propeller

- that can be built into a sailboat bulb keel, an underwater drone or even a sailplane.

Above results from the full scale CFD test for the prototype version showed good correlation with the standard B series investigation thatwas also made. The results are not exactly the same but that was also not expected, as the blade design on the VanishProp is very far from being standard. The relatively low blade area ratio (about 22 %) and the extreme back skew of the blades together with the very special rake that able the blades to “collapse into each other” does not destroy the propellers ability to deliver adequate thrust and also with a very high efficiency.

A VanishProp made for a bulb keel with only 300 mm in diameter will have a propelled outer diameter of 700 mm. This relationship will be the same for all sizes. It will however be possible to make a VanishProp with more blades and thereby a better area-ratio. The above shown case shows a good balance between thrust, speed and bulb size.

Please contact us for further calculations regarding other bulb diameters. Please note that the VanishProp can be build in in either end of the bulb or in both if desired,

Picture hereunder shows the newly milled housing for the prototype VanishProp