>>2948978
>Are there any good resources/books/chapter of book that explain how to properly design fan blades/propeller?
no. went all the way through fluid dynamics ME310 and never once did we look at propellers.

Balance is more important than shape, you can just tilt flat planes and make blades to start with. curving the plane surface and flattening the curve as you go out (probably to provide rotational speed consistency, if it was strength from the distance house fans wouldn't also get bigger blades as the angle of attack lessened)

you aren't going to make a more efficient blade without advanced modeling and you also aren't going to go too wrong aping any existing cooling fan- just wear eye protection when you fire them up, grenading thin plastic is no joke.