Subject: How to estimate air flow &velocity thru a rotating ram air scoop

Major  factors  to  consider  when  estimating  how  much (room-temp/68F)  air  
will  be  passing through  a  rotating  (500 rpm) cylinder with 4 inch diameter 
and  2 inch height. A rotating  ram  air scoop  end-positioned on the top 
plate/disc forces  air  down  into  cylinder  body.  Hood scoop  has  
3/4  inch  height  and 1-1/2 inch (1.5)  width. Mouth  of  hood is 
rectangular.  Slant  angle  of  hood's air  impacting plate  is  to  be 
adjusted  for  maximum  air flow.  QUESTION:  Best  angle(s) to  consider?      
A scoop with an appropriately-curved  air  impacting back-plate form is  also  
feasible  for application. 
  In  one desirable  form, a similar but REVERSE facing/oppositely positioned  
air  scavenging  hood  co-operates  to  pull slightly-compresed air that  was  
forced  into  cylinder up  and  out  of said  cup-like  body.  QUESTION;   To  
ESTIMATE  (say +/-10%)  air  flow,  velocities,  and  pressures,  what  are  
the  most  important  factors  I  must include?   
QUESTION;  What  is  the  most  simple/straight-forward  formula  I  can use to 
estimate  air  flow rate, pressures,  velocities?
QUESTION;  If  the  scavenging/reverse-pointing hood is  removed  and  a 3/4  
by 1 1/2 inch  HOLE  in  the  cylinder's  end plate substitutes, are 
calculations/variables greatly  simplified?   What  does formula  then  
become?   Lastly,  cylinder  end  opposite  scoop and  exhaust opening is      
closed.  PLEASE  help.  

Re: How to estimate air flow &velocity thru a rotating ram air scoop