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WP3 – MAIN PROPULSION
Student Aerospace Challenge
(WP3 - Main Propulsion)
Rémy HAYNAU - Maxime JACQUIN - Pierre-Emmanuel RICHARD - Florian WAEBER
Ecole Polytechnique Fédérale de Lausanne, Lausanne
The group of students from EPFL has
executed the sizing of the primary
propulsion system for a suborbital manned
vehicle (VSH). The mission’s objective is to
maximize
the
weightlessness
time
experienced by the passengers, while
keeping in mind the comfort and security
aspects necessary for the flight to be
enjoyable.
Schematics of the trajectory of a manned
suborbital mission
The proposed solution goes through a
systems analysis. The four interdependent
sub-systems are:
the engine power cycle
the combination of fuel and
oxidizer
the nozzle function of the
trajectory
The pooling of the results of each
subsystem allows for the optimization of the
final solution. It is based on the propulsion
performances, the reusability of the module,
the environmental impact and the security of
passengers. The obtained solution is based
on a classic rocket engine architecture: an
expander cycle with regenerative cooling
fed with butane and liquid oxygen.
Special care was given to the choice of the
fuel which converged towards butane for its
good theoretical propulsion and cooling
performances, in addition to being easily
storable. This is what brings this study
which may seem classical at first sight, to an
innovative solution proposition.
The expander cycle with regenerative cooling
The proposed propulsion module is
reusable; this property is obtained by
minimizing mechanical and thermal
constraints within the engine during
operation. The solution offers good
performances while insuring the vehicle’s
structural integrity as well as the
passengers’ security.