Recent content by shaft

it's just a theoretical question. I don't want kill myself . I know that there should be something like an accumulator in the circuit between the second source of energy and the bulb . but I don't know if are necessary other parts

If I have a light bulb that take energy by the normal current of the house but I want connect at the bulb an other part of energy from an other source of electricity but with an inferior Voltage. This circuit will work or no. How to connect the second source of energy to reduce the amount of...

the global hawk have the raytheon electronic systems ISS with a E-O and IR sensors plus a SYthetic Aperture radar (SAR). this are the Performance E-O/IR field of view : visible 5.1 x 5.2 mrad MWIR 5.4x7.3 mrad...

the problem is that i have already small efficiency of the propeller because the velocity of fly is max 30m/s this mean a small advance ratio and a small efficiency and if i decrease the diameter of prop i don't have enough thrust . It's a loop where I don't found a solution for this I am doing...

so if i don't know the characteristic of the engine I can't built a propeller ?

yes you have right, but in the case that I can select the engine after the selection of propeller, in this way it's the propeller that give the characteristics to the engine.

but in the ideal case that I can have always the best engine appropriate for the propeller ?

Two problem to solve. 1) I have 4 propellers built with different airfoils. I have the graphs of coefficient of thrust and efficiency in function of advance ratio. There is a mathematical method to select which one is the best or the only way is just look at graphs 2)I know the maximum thrust...

Hi. I am new on this website and i hope to found interesting discussions and good answers. the website looks very good.