Efficiency of a propeller is defined as the ratio of available power to the engine power which is. . (3). Note, that this definition for efficiency contains the velocity v, which means, that the efficiency approaches zero as the flight speed goes to zero, because the thrust cannot become infinitely large. So this definition is not useful for the special case of static thrust.
1 Compound Fracture: A compound fracture is a fracture in which the injured bone sticks through the skin. 2  Also known as an open fracture, a compound fracture can be a bit more serious in nature.
Compound Fracture â Symptoms, Treatment, and Complications. Compound fractures are not just a type of fracture, but have a completely different entity, when it comes to managing their symptoms and complications. Not only are they prone to develop several complications, but they have some peculiar symptoms, which if noted, herald the onset of a multitude of interventions by several specialist surgeons.