A liquid rocket engine cools a thruster body by pumping propellant through cooling channels integrated in the thruster body between internal and external surfaces. One or more of the cooling channel surfaces has a variable depth along a thrust axis to mix propellant flow and destroy thermal stratification, such as a depth that varies with a repeated contiguous sinusoidal form along the thrust axis. Fuel passed through the cooling channels injects from the combustion chamber wall towards a central portion of the combustion chamber to cross impinge with oxygen injected at the combustion chamber head so that a toroidal vortex forms to enhance propellant mixing.

A powerplant is provided that includes a pre-burner, a combustor, a power turbine, a mechanical load and a propellant system. The combustor is fluidly coupled with and downstream of the pre-burner. The power turbine is fluidly coupled with and downstream of the combustor. The mechanical load is rotatably driven by the power turbine. The propellant system is configured to direct fluid oxygen and fluid hydrogen to the pre-burner to provide an oxygen rich fuel mixture for combustion within the pre-burner. The propellant system is also configured to direct the fluid hydrogen to the combustor for combustion within the combustor with oxygen within combustion products received from the pre-burner.

A combustion chamber for a rocket engine, the combustion chamber including a combustion chamber body enclosing a combustion chamber volume and a nozzle portion tapering in a longitudinal direction of the combustion chamber and adjoining the combustion chamber body. The combustion chamber body has at least one first portion and a second portion, wherein an inner surface of the at least one first portion facing the combustion chamber volume is closer to a cross-sectional center of the combustion chamber body than an inner surface of the second portion of the combustion chamber body. Furthermore, a additive layer manufacturing method for manufacturing such a combustion chamber is described.

A combustion chamber for a rocket engine, the combustion chamber including a combustion chamber body enclosing a combustion chamber volume and a nozzle portion tapering in a longitudinal direction of the combustion chamber and adjoining the combustion chamber body. The combustion chamber body has at least one first portion and a second portion, wherein an inner surface of the at least one first portion facing the combustion chamber volume is closer to a cross-sectional center of the combustion chamber body than an inner surface of the second portion of the combustion chamber body. Furthermore, a additive layer manufacturing method for manufacturing such a combustion chamber is described.

A variable flow area injector for a liquid rocket engine. The injector has a poppet with a variable outer width portion and a housing with a variable inner width portion. An annular flow path is defined between the variable width portions. Increased throttling of the engine passively increases the annular flow area of the injector by forcing the poppet in a distal direction. Decreased throttling allows a restoring spring to move the poppet in a proximal direction to decrease the annular flow area. A bellows can be included to dampen movement of the poppet. The bellows may be in a propellant-filled cavity separate from the main propellant flow path and have a series of openings through which the separate propellant flows.

A rocket engine includes a copper alloy combustion chamber, a non-copper weld transition ring welded to the copper alloy combustion chamber, and an injector assembly welded to the non-copper weld transition ring. The engine can be manufactured by forming the copper alloy combustion chamber using additive manufacturing, welding the non-copper weld transition ring to the copper alloy combustion chamber, and welding the injector assembly to the non-copper weld transition ring.

A rocket engine includes a copper alloy combustion chamber, a non-copper weld transition ring welded to the copper alloy combustion chamber, and an injector assembly welded to the non-copper weld transition ring. The engine can be manufactured by forming the copper alloy combustion chamber using additive manufacturing, welding the non-copper weld transition ring to the copper alloy combustion chamber, and welding the injector assembly to the non-copper weld transition ring.

A method for manufacturing a liquid fueled rocket engine involves forming a first flange in apposition to a top end of a first tube, fixing an injector head to the first flange to form an inner shell liner assembly, shaping the inner shell liner assembly, forming a second flange in apposition to a top end of a second tube, positioning the inner shell assembly inside the second flanged tube and fixing the second flange to the injector head. Rocket engines manufactured using the method have performance superior to existing rocket engines in at least one parameter.

A method for manufacturing a liquid fueled rocket engine involves forming a first flange in apposition to a top end of a first tube, fixing an injector head to the first flange to form an inner shell liner assembly, shaping the inner shell liner assembly, forming a second flange in apposition to a top end of a second tube, positioning the inner shell assembly inside the second flanged tube and fixing the second flange to the injector head. Rocket engines manufactured using the method have performance superior to existing rocket engines in at least one parameter.

A liquid rocket engine cools a thruster body by pumping propellant through cooling channels integrated in the thruster body between internal and external surfaces. One or more of the cooling channel surfaces has a variable depth along a thrust axis to mix propellant flow and destroy thermal stratification, such as a depth that varies with a repeated contiguous sinusoidal form along the thrust axis. Fuel passed through the cooling channels injects from the combustion chamber wall towards a central portion of the combustion chamber to cross impinge with oxygen injected at the combustion chamber head so that a toroidal vortex forms to enhance propellant mixing. The cooling channels are formed by milling at the combustion body exterior, filling the channels with wax, then electroplating metal to enclose the channels.