Hello,
Have you verified that the airflow does not change angular direction with airspeed? Another way of saying this is "are you sure that everything else is constant except for airspeed and angle of attack.
Did some wind tunnel testing years ago and found that the wind tunnel was not...
Hello Sonargod,
I think you may be simulating the ballistics equation and I will dig this up from my notes as I know I cannot quote the equation from memory.
During my school days, we did exactly what you are doing and I wrote a code which simulates pressures, temperature of the gas including...
Hello,
I downloaded Xrotor just for fun from the following site.
http://www.aeromech.usyd.edu.au/AERO4290/docs/xrotor/
It works for me. My operating system is Windows XP.
Hello,
The induced drag is more accurately called "lift induced drag". You are correct that at zero lift (cl = 0), the lift induced drag would be zero. But the total drag will not be zero.
Also, the formula for lift induced drag is more accurately:
Cd(lift induced) = cl^2/(Pi * e * AR)...
Hello Mohr,
The book, Ducted Fan Design, which also has notes on propeller design, recommends designs for propellers such that the operating point is below 80% of the stalling angle.
I do not know of any book or publication that has post stall airfoil behavior.
There are several propeller design programs (ie. Blade Gen, CFX, etc.) One can also write a potential flow program to determine blade profile, possible selecting a profile at an angle to minimize induced drag.
There are several documents on this subject (freely available) at the NASA document...
Regarding Canadian Universities - you might want to ask local aerospace companies (ie. Bombardier, Pratt & Whitney, etc) what they would recommend. I liked in order Ryerson University, Carlton University and University of Toronto. I know that Ryerson introduced in their Aerospace program...
Second the motion: The book by Jean-Claude Flabel, "Practical Stress Analysis for Design Engineers" is superb. His website is www.psa1.com. I recently ordered the book and I would highly recommend it along side of Bruhn.
Shirajpn,
Isentropic flow in general terms means a flow with no lossess (no friction, no heat transfer losses,etc). It is a flow with no entropy change.
The assumption of isentropic flow greatly simplifies the mathematical model used to describe the flows be it subsonic, transonic or supersonic.
I would be interested in seeing a FAQ for stress as well. I recall seeing a Boeing Stress manual - never had the chance of using it.
As to getting tired of answering the same questions - now you know how your prof's felt and how your supervisors felt when you were at your first real job.
