Alpha-Centauri mission

Analysis of simple straight-line mission. Not time-resolved. Acceleration and deceleration. Assumes a nuclear fusion powered rocket burning the fuel of Helium-3 and Deuterium. ------------------------------------------------------------------------- See also AtomicMass, RocketMass, Constant -------------------------------------------------------------------------

%------------------------------------------------------------------------
%   Copyright 2017 Princeton Satellite Systems, Inc.
%   All rights reserved.
%------------------------------------------------------------------------

% Mission parameters
%------------------
duration	= 700; % Years
power     = 20e6; % Watts
mP        = 500;
secInYear = 86400*365.25;
eta       = 0.6;
fUE       = 0.12;

% Spacecraft parameters
%----------------------
sP        = 1.4; % kW/kg
fS        = 0.005; % Structural fraction
uFusion   = 2.4e7; % Fusion product velocity, m/s
uE        = fUE*uFusion;
mPP       = power/1000/sP;
mDry      = mP + mPP;

% Constants
%----------
c         = Constant('speed of light');
lightYrs  = 4.5;

% Distance
%---------
d         = lightYrs*c*secInYear;
v         = d/(duration*secInYear);
f         = v/c;
dV        = 2*v;

[mF, mT, mS, e]   = RocketMass( uE/9.806, mDry, fS, dV );

thrust            = 2*power*eta/uE;

tA                = v*(mDry + 0.75*mF)*1000/thrust/secInYear;
tD                = v*(mDry + 0.25*mF)*1000/thrust/secInYear;


fprintf(1,'Power               %12.1f (MW)\n',power/1e6);
fprintf(1,'Specific Power      %12.1f (kW/kg)\n',sP);
fprintf(1,'Duration            %12.1f (yr)\n',duration);
fprintf(1,'Velocity            %12.1f (km/s)\n',v);
fprintf(1,'Time to Accelerate  %12.1f (yr)\n',tA);
fprintf(1,'Time to Deccelerate %12.1f (yr)\n',tD);
fprintf(1,'Exhaust Velocity    %12.1f (km/s)\n',uE/1000);
fprintf(1,'Thrust              %12.1f (N)\n',thrust);
fprintf(1,'Mass fuel           %12.1f (kg)\n',mF);
fprintf(1,'Mass payload        %12.1f (kg)\n',mP);
fprintf(1,'Mass power plant    %12.1f (kg)\n',mPP);
fprintf(1,'Mass Dry            %12.1f (kg)\n',mT-mF);


rho             = 0.1785e-3; % kg/liter at stp http://scratchpad.wikia.com/wiki/Helium-3
he3             = AtomicMass('he3','kg');
ePerReaction    = 18.35; % MeV, for D-3He fusion
mEVToJ          = 1.60217646e-19*1e6;
jPerKg          = ePerReaction*mEVToJ/he3;
kgHe3           = power*(tA+tD)*secInYear/jPerKg;
volHe3          = kgHe3 /rho;

fprintf(1,'Mass he3           %12.1f (kg)\n',kgHe3);
fprintf(1,'Volume he3         %12.1f (l)\n',volHe3);


%--------------------------------------
% PSS internal file version information
%--------------------------------------

Power                       20.0 (MW)
Specific Power               1.4 (kW/kg)
Duration                   700.0 (yr)
Velocity                  1927.2 (km/s)
Time to Accelerate         340.2 (yr)
Time to Deccelerate        185.6 (yr)
Exhaust Velocity          2880.0 (km/s)
Thrust                       8.3 (N)
Mass fuel                42177.4 (kg)
Mass payload               500.0 (kg)
Mass power plant         14285.7 (kg)
Mass Dry                 14996.6 (kg)
Mass he3                  565.3 (kg)
Volume he3            3166912.8 (l)

Published with MATLAB® R2019a