Abstract: An intermediary chamber associated to a device for feeding a pulsatory combustion chamber with fuel and comburent includes a heat tube l65 defining with the inner channel wall 125 a recirculation zone for the burnt gases issuing from the combustion chamber. The intermediary channel located between the combustion chamber for pulsatory combustion of a mixture of fuel and a combustive agent and an injection chamber includes the heat tube being directly communicated with the combustion chamber, wherein an internal wall of the intermediary channel and an outer surface of the heat tube define a recirculation zone for the recirculaton of burn gases issuing from the combustion chamber, the recirculation zone being at least partially open at an upper end thereof.