Contents

Mission capability chart using straight-line trajectories

Solve for 2D straight-line trajectories to Jupiter, Pluto, and 125 AU

See also: EngineThrust, ComputePayload, InitialMass, Straight2DStructure

%--------------------------------------------------------------------------
% Copyright (c) 2018 Princeton Satellite Systems, Inc.
% All rights reserved.
%--------------------------------------------------------------------------

% Constants
year = 365.25*86400;    % s
au   = Constant('au');  % km

% Engine parameters
d = Straight2DStructure;
d.f = 0.05;     % kg tank/kg fuel
d.eta = 0.4;    % efficiency to jet thrust
d.sigma = 1000; % W/kg
d.uE = 120;     % km/s
d.mE = [];

Jupiter

T/W is 2.01e-3 m/s2

d.dF = 5.2*au;
d.tF = 1*year;

[lambda,alpha] = ComputePayloadFraction(d);

% Power range, MW
powers = linspace(0.5,30,30);
mPJ = alpha*powers*1e6;
m0 = mPJ/lambda;
TW(1) = EngineThrust(powers(1)*1e6, d)./m0(1);

hF = Plot2D(powers,mPJ,'Power (MW)','Payload Mass','DFD - 1000 W/kg, 100 km/s, N~0.4');
hold on;
hA = gca;
Plot2D(powers,m0/1e3,'Power (MW)','Initial Mass (MT)','Jupiter')

Pluto

T/W is 5.05e-4 m/s2 for 5 years

d.dF = 40*au;
d.tF = 5*year;
[lambda,alpha] = ComputePayloadFraction(d);

powers = linspace(0.5,6,30);
mPP = alpha*powers*1e6;
m0 = mPP/lambda;
TW(2) = EngineThrust(powers(1)*1e6, d)./m0(1);

plot(hA,powers,mPP)
Plot2D(powers,m0/1e3,'Power (MW)','Initial Mass (MT)','Pluto')

Extrasolar

T/W is 2.9e-4 Check the values of payload mass - this says 1000 kg can go to 125 AU with these engine parameters but the thrust solver says a uE of 120 km/2 is needed.

d.dF = 125*au;
d.tF = 10*year;

[lambda,alpha] = ComputePayloadFraction(d);

powers = linspace(2,30,30);
mPE = alpha*powers*1e6;
m0 = mPE/lambda;
TW(3) = EngineThrust(powers(1)*1e6, d)./m0(1);

plot(hA,powers,mPE)
Plot2D(powers,m0/1e3,'Power (MW)','Initial Mass (MT)','Extrasolar')
legend(hA,'Jupiter - 1 year','Pluto    - 5 years','125 AU - 10 years')

disp(table(TW','RowNames',{'Jupiter','Pluto','Extrasolar'},'VariableNames',{'T/W (m/s2)'}))


%--------------------------------------

% $Id: 8b6287a25a09716d55ee4e565d93417a360b1cb7 $

                  T/W (m/s2)
                  __________

    Jupiter        0.0021503
    Pluto         0.00055509
    Extrasolar    0.00033659

Published with MATLAB® R2024a