Jet engine, flying object, and operation method of jet engine

A flying object comprising a jet engine which comprises:

• an inlet configured to introduce air;
• and
• a combustor having a fuel injection port from which a fuel is injected and configured to combust the fuel injected from the fuel injection port by using the air,
• wherein the combustor comprises a separation section defining an air passage through which the air flows, between a rear end of the inlet and the fuel injection port,
• wherein a plurality of turbulent flow generating sections are arranged in the separation section to make an air flow in the air passage turbulent, and
• wherein each of the plurality of turbulent flow generating sections comprises:
• a first member configured to create turbulence in a boundary layer of the air flow on a wall surface of the separation section as it protrudes from the wall surface towards the air passage, and to lessen the turbulence in the boundary layer of the air flow by moving from a first position in which the first member protrudes from the wall surface of the separation section to a second position in which the first member lies against the wall surface of the separation section;
• and
• a second member configured to support the first member in the first position, and further configured to disappear automatically from the wall surface of the separation section by a thermal influence or an aerodynamic influence in flight so that the first member moves automatically to the second position.

An operation method of a jet engine,

• wherein the jet engine comprises:
• an inlet configured to introduce air;
• and
• a combustor having a fuel injection port from which a fuel is injected and configured to combust the fuel injected from the fuel injection port by using the air,
• wherein the combustor comprises a separation section defining an air passage through which the air flows, between a rear end of the inlet and the fuel injection port, and
• wherein a plurality of turbulent flow generating sections are arranged in the separation section to make an air flow in the air passage turbulent,
• the operation method comprising:
• combusting the fuel injected from the fuel injection port by using the air while making a boundary layer of the air flow on a wall surface of the separation section turbulent by first members of the plurality of turbulent flow generating sections respectively protruding from the wall surface toward the air passage in a first stage of operation;
• automatically moving the first members of the plurality of turbulent flow generating sections from a first position in which the first members are supported by second members of the plurality of turbulent flow generating sections and protrude from the wall surface of the separation section to a second position in which the first members lie against the wall surface of the separation section by an automatic disappearance of the second members due to a thermal influence or an aerodynamic influence in flight;
• and
• combusting the fuel injected from the fuel injection port by using the air while lessening turbulence in the boundary layer of the air flow on the wall surface of the separation section in a second stage of operation.