I'm trying to to find some information on case fan design on straight blades vs curve blades. What's the difference in the two blade design? To be more specific, I was looking at Yate Loon's fans as they have a curved blades and straight blades version of the same model fan. Here's a picture to be more specific:
generally speaking, the curved fin design makes for less air resistance than the straight does. meaning lower noise, and power requirements for moving the air. it also gives for a tinny bit more surface area.
From my browsing of Silent PC Review it seems that you get less turbulence and noise if the edge of the fan blade is at right angles to the motor support rod as it sweeps by it. Here's a rundown of their anatomy of a silent fan - page 3 has some pretty detailed information on blade design.
Looking at the article, taking in your inputs, and examining the two blade design from my picture, the curve tailing edge blades looks like it would scope up more air by having a curve surface than the almost flat surface of the straight blade. As far as turbulence from the tailing edge of both blade being parallel when they cross, that's not applicable to either fans.
Right now the curve blades fan would be my best choice. If anyone else have more to add, please help out.
I like the design Noctua puts out but as far as price and performance, Yate Loon beats them by far. At first I worked out my fans around Noctua's P12 and different fans from Noisebloocker which both brands offer 6 year warranty and $20+ price per fan. If I get them for both of my CM 690 and HAF 932 cases, I would be spending around $300 for four fans for my CM 690 and eight fans for my HAF 932. Where as if I get Yate Loons, I would be spending a fraction of the price for them of around $30+.
Yes there are better option but Yate Loon are highly rated fans that deliver outstanding performance for the price. Concerning the design question, Noctua offer a great design to reduce Vortex Shredding with their fans but the site does not provide specific answer to the different blade design I asked.