trajectory

# SI units

3 # dimensions

# gravity: Earth
# GM=398,600.4418 => G=
newtonian 6.67384e-11 5.97219e24 6371e3 # G M R

# environment
# scale-height atmosphere
separable_map # rho(r) Function3D
   power 2 power 2 power 2 # rprime_i(r_i): r_i**2
   # m(f(rprime(r))): rho0 exp(-(r-rsurf)/h) : r = sqrt(f(rprime))
      nested 4
         scale 1.2 # rho0
         exp
         polynomial 2 796.375 -0.125e-3 # rsurf/h -1/h ie 6371e3/8.0e3 -1/8.0e3
         sqrt
   1dsum scale 1.0 scale 1.0 scale 1.0 # f(rprime): sum
constant 0.0 constant 0.0 constant 0.0 # u_i(r) Function3D[3]

# hard deck
sphere   0.0 0.0 0.0   6371e3

# rocket
constant 1.0 # Cd(u,t): typical hypersonic sphere
constant 0.5 # frontal area (mass,time)
constant 0.0 # volume (mass, time)
constant 0.0 # F(t)
constant 1.0e10 # alpha: F = -alpha dm/dt cf F Dt=D(m u_x) => F = u_x dm/dt => alpha = u_x
constant 1.0e8 # max structural pressure (mass,time), ~2 x strength for uniform body
constant 0.0 # ablation rate (fdrag = pdrag * area, gas rho, rocket mass)

# launcher
none

# initial state
0.0   42164e3 0.0 0.0   0.0 1.586e3 0.0  100.0 # t r u m

# integration
5e6 10 # 259200.0 100.0 # dt dtsub

end