Recent content by sandhammaren

A surface-piercing propeller is not simply one running half in and half out of the water. It is any propeller where the blade tips or any part of the blades pierce the water surface each revolution. This eliminates cavitation and reduces drag. All racing props are surface-piercing.

Based on your statements, I seriously doubt that you understand hydrodynamics very well, unfortunately. Your screwy explanation dates to ca. 1900. Juynior officers in a war room surely do not understand hydrodynamics. The use of 'screw' for propeller is a historically fixed term that is, from...

Beware people who've read something and imagine they understand it. No propeller, period, works like a screw, and naval architects know that. Efficiency, high thrust/drag is achieved only via circulation about the blade. Make yourself familiar with the literature and phenomena before claiming to...

Look, I don't merely know hydrodynamics, I raced successfully for 13 years (5 national championships, 2x U.S.-1, 3 speed records). A propeller is not at all like a screw, it operates via circulation (providing high lift/drag) like an airfoil, hydrofoil, or sail. Understanding the drag is...

Only rough rules based on scaling/empirical constants are known. See Dave Gerr's Propeller Handbook. Racing props require extensive trial and error. Physics Prof who raced outboards successfully

Martingales are nonstationary Martingales are nonstationary processes (with one singular exception) and martingale differences/increments are generally nonstationary. If the increments are stationary then there is (i) no ergodicity and (ii) no i.i.d. unless the diffusion coefficient is both...