The effect of lift on aeroassisted orbital transfer trajectories
Boyle, Philip P.
Master of Science
Miele, Wang, and Deaton have demonstrated in Ref. 1 how optimal trajectories are produced by eliminating positive lift and fixing the lift coefficient at its lower, negative (downward) bound all throughout the atmospheric pass. Because of this fixed control, the problem is posed here as a highly nonlinear two-point boundary-value problem (TPBVP) which is solved by enlisting a multipoint version of the modified quasilinearization algorithm. This thesis supplements Ref. 1 by performing trade studies showing how all the performance indices improve with decreasing lift coefficient lower bound, that is, more negative lift. We also formulate a two-subarc TPBVP for the purpose of testing the effect of a short period of positive lift applied during the descent phase followed by a switch to negative lift. The result is that all performance indices worsen when any positive lift is applied compared to the constant negative lift coefficient case.
Aerospace engineering; Computer science