I'll have to play with this. I don't doubt what you are saying at all. I've been lazy, I said FEA when I meant FEA and CFD, we have both available and yes, boundary layer effects and vortex flows are taken into account. Fun stuff to play with. For some problems you could spend your entire life simulating and never reach a conclusion!
I'll repeat my warning that I am not an aero engineer and what I've learned has lots of holes here and there.
As I understand it, boundary layer control is difficult. I remember going through NASA papers that talk about techniques used in centrifugal superchargers to control the boundary layer. These are impellers running at speeds way beyond that of the proposed heatsink. If I remember correctly, one of the problems with various techniques is that of flow separation. This would cause large portions of the blade surface to, effectively, not exchange any heat to speak of with the separated flow. Airfoil choice is important here.
That said, the proposed heatsink does not, as its primary design intent, have the requirement to be a good pump. The primary design requirement is to opimize heat transfer to the surrounding air. Things can and probably do change when you are optimizing for that.
What I would really like to see is the performance of a complete design. One that includes a casing with suitable inlet and outlets as well as the required safety devices. In my limited experience, that's when things can start to change. For example, the nature of the intake airflow can greatly affect what happens when the airflow hits the vane leading edge and beyond. Also, noise levels can go up.
It'd be interesting if someone in aerodynamics could pitch-in and talk about some of these effects and how things can change outside of simulations and free-air environment prototypes.
I'll repeat my warning that I am not an aero engineer and what I've learned has lots of holes here and there.
As I understand it, boundary layer control is difficult. I remember going through NASA papers that talk about techniques used in centrifugal superchargers to control the boundary layer. These are impellers running at speeds way beyond that of the proposed heatsink. If I remember correctly, one of the problems with various techniques is that of flow separation. This would cause large portions of the blade surface to, effectively, not exchange any heat to speak of with the separated flow. Airfoil choice is important here.
That said, the proposed heatsink does not, as its primary design intent, have the requirement to be a good pump. The primary design requirement is to opimize heat transfer to the surrounding air. Things can and probably do change when you are optimizing for that.
What I would really like to see is the performance of a complete design. One that includes a casing with suitable inlet and outlets as well as the required safety devices. In my limited experience, that's when things can start to change. For example, the nature of the intake airflow can greatly affect what happens when the airflow hits the vane leading edge and beyond. Also, noise levels can go up.
It'd be interesting if someone in aerodynamics could pitch-in and talk about some of these effects and how things can change outside of simulations and free-air environment prototypes.