Reduced cost membrane seal assembly for pulsed rocket motor

Abstract

A membrane seal assembly separating forward and aft combustion chambers of a rocket motor. The assembly covers the aft surface of a bulkhead having apertures therein to preclude flow communication between the combustion chambers during combustion of propellant within the aft combustion chamber. The assembly includes a membrane which has a plurality of sectors which open along hinge lines away from the bulkhead to allow flow communication between the combustion chambers when a higher pressure is present in the forward combustion chamber than in the aft combustion chamber, i.e., during subsequent combustion of the propellant in the forward combustion chamber. The sectors are provided by a plurality of radially extending slits in the membrane which are formed entirely through the thickness of the membrane so that complex scoring tooling and close tolerances of manufacturing membranes with score lines is not required while maintaining reliability of the burst membrane so that the cost of the membrane seal assembly may be reduced. The pattern and sizing of apertures in the bulkhead is such, for an erodible bulkhead, that each aperture erodes into the adjacent eroding apertures in such a manner as to minimize the size of debris breaking away from the bulkhead to reduce the possibility of debris becoming lodged in the nozzle throat.