|
|
Ok, here are the comparsion of the streamline diffuser and the one with
parabolic curved walls. This may help a bit. NOTE: Both the dynamic pressure
(yellow curve) and duct area (blue curve) are now measured against the right
Y axis. The left Y axis shows the duct wall distance from the duct axis at
the x point shown. So it is 1/2 of the distance from wall to wall. So area
= (2*Y)^2
The Red curve reflects the Y coordinates of the duct wall from the
centerline of the duct axis with values shown on left Y axis. The blue
reflects the Area of that duct at the x location shown on right Y axis
(ft^2). The yellow curve shows the dynamic pressure at various points along
the x axis of the duct with values displayed on right Y axis (Psi)..
The point being that most things in nature that are linear seem (from my
long ago school days) to have less losses that process which are non-linear.
That is one of the reasons that most examination of physical processes
initially assume that they are at lower energy levels they makes assuming
they are linear process close enough to reality for analytical purposes
(makes for simpler analysis).
Interestingly the parabolic curve generates a linear area increase but a
parabolic dynamic pressure increase. The streamline curve generates what
appears to be an expontential (or at least curved) area increase which
results in a linear increase in dynamic pressure.
Yawn. Just had a lobster and Crab Leg dinner that was to kill for. Got
some assembly to do on a few presents for the Grandchildren. So Merry
Christmas to all.
Ed Anderson
RV-6A N494BW Rotary Powered
Matthews, NC
eanderson@carolina.rr.com
|
|