Re: Roundovers on leading and trailing edges of rudder.
Posted: Thu Oct 30, 2014 5:37 pmYes...no...well.....
More complicated geometry=more complicated construction. But, while making PocketShip's rudder's trailing edge sharp instead of blunt might technically reduce drag a little, you'll never see it in the performance of the boat.
In terms of shaping the rudder, there would be a benefit to a NACA0012-shaped foil for a spade rudder, or for a rudder that extended below the keel. For Pocketship's geometry, the rudder is essentially part of the airfoil shape of the keel, similar to how a rudder on an airplane is part of the airfoil shape of the vertical tail. In this case, the single best thing you could do to increase rudder effectiveness is to minimize the gap between the trailing edge of the keel and the leading edge of the rudder. I've imagined even a few schemes to add a wiper seal between the two. But, PocketShip's rudder is totally capable, so It have never seen a need to implement the idea, other than geekiness.
More complicated geometry=more complicated construction. But, while making PocketShip's rudder's trailing edge sharp instead of blunt might technically reduce drag a little, you'll never see it in the performance of the boat.
In terms of shaping the rudder, there would be a benefit to a NACA0012-shaped foil for a spade rudder, or for a rudder that extended below the keel. For Pocketship's geometry, the rudder is essentially part of the airfoil shape of the keel, similar to how a rudder on an airplane is part of the airfoil shape of the vertical tail. In this case, the single best thing you could do to increase rudder effectiveness is to minimize the gap between the trailing edge of the keel and the leading edge of the rudder. I've imagined even a few schemes to add a wiper seal between the two. But, PocketShip's rudder is totally capable, so It have never seen a need to implement the idea, other than geekiness.