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#227087
If you have any resources for me to check out along these lines, let me
know! Calculus O.K.
Looking for all manner of stuff, wing loading, g force, wing dynamics, structural.
Please no programs, encyclopedias, joke. Just the equations, thanks!
Last edited by Phoenix on Tue Mar 08, 2011 8:29 am, edited 1 time in total.
User avatar
By mlbco
#227106
Here's some Matlab code to estimate a glider's polar.

Steve

%Polar Estimation MATLAB Code
%SJM 3-5-11
close all;clear all;
torad=pi/180.;
d2r=torad;
grav=32.174;
%-------------------------------------
%T2C
weight=70.0+200; %Gross weight (lb)
bref=33.5; %wing span (ft)
sref=154.0;%wing area (ft^2)
fo=1.75;%Non lifting drag area (ft^2) This accounts for pilot, downtubes, rigging, instruments, etc.
clmax=1.3; %Stall CL
clmin=0.2; %dive CL
cdo=.01; %zero lift drag for the wing section
cd2=.005; %lift dependent viscous drag for the wing section
ro=0.00237; % air density (slug/ft^3)
e=0.9; % span efficiency factor (0<e<1)
bank=0.0*torad; %bank angle (deg) (use this to estimate polar in turing flight i.e. thermalling)
%-------------------------------------
%------------------------------------------
ar=bref*bref/sref;
num=100;
dcl=clmax/num;
for i=1:num
cl=clmax-dcl*(i-1);
if(cl>clmin)
cd=fo/sref+cdo+cl*cl*(cd2+1./(pi*ar*e)); %drag coeff
vo(i)=sqrt(2.*weight/(ro*cl*sref*cos(bank)));%Airspeed at trim CL (ft/sec)
drag=0.5*ro*vo(i)*vo(i)*cd*sref; %Drag (lb)
vv(i)=(-drag*vo(i)/weight);%sink rate (ft/sec)
radius(i)=1e6;
if(bank>0)
radius(i)=vo(i)*vo(i)/(grav*tan(bank));%Turn Radius (ft)
end;
phi(i)=bank/torad;% Bank angle(deg)
ld(i)=vo(i)/-vv(i);%L/D w.r.t. air
gam(i)=atan(1/ld(i))/d2r; %Glide angle (deg)
%ld2(i)=cl*cos(bank)/cd;
end;
end;
figure(1);plot(vo/1.467,ld,'-b');zoom on;grid on; %L/D vs airspeed (mph)
figure(2);plot(vo/1.467,60*vv,'-b');zoom on;grid on; %Sink rate (fpm) vs airspeed (ft/sec)
User avatar
By AIRTHUG
#227114
:run:
By Phoenix
#227128
No mat lab. But I do have mathematica circa 2006. Also mathcad circa 2001.
Not into programing much, just the equations.
User avatar
By st1lgar
#227133
now having the polars you can calc mccready...
look here :)
http://faculty.chicagobooth.edu/john.co ... wmcred.pdf
By Phoenix
#227143
st1lgar wrote:now having the polars you can calc mccready...
look here :)
http://faculty.chicagobooth.edu/john.co ... wmcred.pdf
now having the polars???? I can not decode MATLAB! I don't do programing!!!
I will read the mccready article though.
Just asking for formulae that apply to HG, (from simple stuff to polars) not the entire volume of mathematics from pythagoras to Andrew Wiles, now sorry I asked! :cry:
By Phoenix
#227168
deleted
Last edited by Phoenix on Sun Mar 06, 2011 4:40 am, edited 1 time in total.
By Phoenix
#227169
Deleted
Last edited by Phoenix on Sun Mar 06, 2011 4:42 am, edited 1 time in total.
By Phoenix
#227170
Deleted-caught by the server down
Last edited by Phoenix on Sun Mar 06, 2011 4:44 am, edited 3 times in total.
By rongleason
#227200
checking account = x
start HG
buy equipment, buy new vehicle, convince the SO to camp and drive

checking account now = x-(HG equip - vehicle - gifts to keep SO happy) + 50% of usual paycheck due to number of sick days taken

long HG trips, quit job, SO leaves etc

checking account has been closed and live off the cash in the wallet

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