Originally Posted by
mustangman177
Yeah, I know what you're saying.....He knows I'm into modeling, and the students father/grandfather are older modelers themselves, so the student already has a interest in model aviation that I believe can be cultiated. Kid has a lot of potential and I like the experiment he is attempting--Something new and refreshing- instead of the old same experiments that always gets repeated.
I searched the web for 2-3 prop blade efficiency-thrust and could not find "Hard data" that he could use in a Review of Literature......May have to look at this another way.
Thanks again to all that helped..... May have another "Rocket Boy" here?
Cary
Well, I like this kid....Kudos to you for the encouragement
Although hard data may or may not exist (Boeing and NASA websites perhaps?), the experimental phase should be straight forward.
The way I would approach it is to make a 3 bladed prop from 2 bladers (wood would be easier of course), to make certain important factors such as blade shape, area, thickness, stiffness and construction are as identical as a CNC mill can reproduce. He should employ the school's machine shop to cut the wood and fit the wood with precision and also employ his more experienced family members to assemble the 3 blader precisely.
The experiment may require a couple different diameters and pitches to produce a reasonable matrix of outputs. It may be simpler to just ask Falcon props or Xoar to produce what's needed.....
A single electric motor of adequate capacity should be used for the whole batch of props. Great thing about emotors, you can get very precise measurements of current draw regardless of where in the power curve the thing is turning. Will need to get a temp read on all electrical components but the heat effects may be minimal if enough capacity is used
A common esc should be employed, that's driven by an accurate power supply. Or, perhaps simpler, have a power supply with variable output of voltage, while allowing current to float
Thrust is the measured output. Amps draw is the slave output for any given voltage. Watts to be calculated. Or make thrust constant and see where the other parameters fall
A controlled environment should be used such as the school's airconditioned and humidity controlled gym, cafetorium, whatever, where the tests can be done unobstructed and where walls are far enough away not to interfere with thrust measurements.
That's it. Good luck......Would love to see the results in MA