Ed,
Some of us real "radical" rotor heads are using the
2.85:1 ratio drive. I was wondering if you could
modify your spreadsheet model to allow other drive
ratios? This may help some of us to better model our
systems and make the proper choices for the other
system components.
Thanks,
Jim Maher
(Dyke Delta/13B)
--- Original Message ---
From: "Ed Anderson" <eanderson@carolina.rr.com>
To: "Rotary motors in aircraft"
<flyrotary@lancaironline.net>
Subject: [FlyRotary] New cooling Model example

>Ok Folks,
>
>    I've been messing around with the cooling model
of the spreadsheet that
>some of you have.
>I don't want to send out dozens of spreadsheets which
are in the development
>phase and have 47 different version out there.  So I
am only going to send
>out some results of the latest models in the
spreadsheet and ask for
>comments.
>
>Once it appears that the model is approaching some
degree of realism and
>usefulness, then I will be happy to provide everyone
with it.
>
>Right now, I am concentrating on the evaporator core
models.  However, my
>intention - if it works out with the cores - is to
broaden this so other
>folks not using the cores can make use of it as well.
>
>I realize that some of you may not have much more
insight into what
>"realistic" might intale than I do, but I have a
great deal of faith in the
>keen analytical minds out there to provide some
useful input (How about that
>for stroking the egos{:>))
>
>I have attached a spreadsheet with the results of  
three cases using the
>model.  The all involve an aircraft taking off in
early climb out producing
>150 HP.  The three cases involve climb out, high
power and low airspeed.
>Case 1.  Climbout is made on a 20F day with 150HP at
just fast enough
>airspeed to provide minimum adequate cooling.  
Case2.  Climbout is made on a
>90F day with the same power and airspeed conditions
as case 1.  The model
>shows the cooling capacity is exceeded.  Case 3.  
Then holding everthing the
>same  as case 2 including power and 90F OAT, I
increase the airspeed (and
>therefore mass flow) until at 117 MPH we again barely
achieve adequate
>cooling on the 90F day.  Note that the delta T
changes for each case.
>
>There are some comments and notes with each case.  
Take a look and if
>inclinded I would greatly appreciate any feedback.
>
>
>Ed Anderson
>RV-6A N494BW Rotary Powered
>Matthews, NC
>eanderson@carolina.rr.com